Global analysis of RNA expression profile in human vascular cells treated with statins

KLF4 and CD55 expression and function depend on each other

The transcription factor Kruppel-like factor 4 (KLF4) regulates the expression of immunosuppressive and anti-thrombotic proteins. Despite its importance in maintaining homeostasis, the signals that control its expression and the mechanism of its transactivation remain unclarified. CD55 [aka decay accelerating factor (DAF)], now known to be a regulator of T and B cell responses, biases between pro- and anti-inflammatory processes by controlling autocrine C3a and C5a receptor (C3ar1/C5ar1) signaling in cells. The similarity in CD55's and KLF4's regulatory effects prompted analyses of their functional relationship. In vascular endothelial cells (ECs), CD55 upregulation accompanied KLF4 expression via a p-CREB and CREB Binding Protein (CBP) mechanism. In both ECs and macrophages, CD55 expression was essential for KLF4's downregulation of pro-inflammatory/pro-coagulant proteins and upregulation of homeostatic proteins. Mechanistic studies showed that upregulation of KLF4 upregulated CD55. The upregulated CD55 in turn enabled the recruitment of p-CREB and CBP to KLF4 needed for its transcription. Activation of adenylyl cyclase resulting from repression of autocrine C3ar1/C5ar1 signaling by upregulated CD55 concurrently led to p-CREB and CBP recruitment to KLF4-regulated genes, thereby conferring KLF4's transactivation. Accordingly, silencing CD55 in statin-treated HUVEC disabled CBP transfer from the E-selectin to the eNOS promoter. Importantly, silencing CD55 downregulated KLF4's expression. It did the same in untreated HUVEC transitioning from KLF4low growth to KLF4hi contact inhibition. KLF4's and CD55's function in ECs and macrophages thus are linked via a novel mechanism of gene transactivation. Because the two proteins are co-expressed in many cell types, CD55's activity may be broadly tied to KLF4's immunosuppressive and antithrombotic activities.

Neuroprotective effects of pravastatin in cerebral venous infarction in a rat model

Objectives

Pravastatin sodium is reported to have multiple beneficial effects in cerebral atherosclerosis and neuronal injury; however, the preventive effects on cerebral venous ischemia are still unknown. Herein, we aimed to examine the neuroprotective effects of transoral prior administration of pravastatin sodium against cerebral cortical venous ischemia with suppression of apoptosis.

Methods

Thirty 8-week-old male Wistar rats were divided equally into two study groups (n = 15 vs. n = 15); the pravastatin group was fed 1% pravastatin sodium with their usual diet for 2 weeks, while the control group only received the usual diet. Two-vein occlusion (2VO) model was applied for this study, and two adjacent cortical veins in each animal were permanently occluded photochemically with rose bengal dye. During photo-thrombosis, regional changes of the cerebral blood flow (CBF) in area of the venous ischemia were recorded. At 48-h after 2VO, animals were euthanized using perfusion fixation, and we histologically measured ratios of infarcted area to contralateral hemisphere, and counted Bax- and Bcl-2-positive cells in the penumbra to investigate the implications for apoptosis.

Results

The ratio of infarcted area was significantly decreased in the pravastatin group compared to the control group (P < 0.01). The number of Bax-positive cells also decreased significantly in the pravastatin group (P < 0.01). In contrast, immunolabeling for Bcl-2 was essentially negative in all areas in both groups. There were also no significant differences in regional CBF changes after 2VO between the two groups (P = 0.13).

Conclusions

Pre-emptive administration of pravastatin sodium mixed in the food has neuroprotective effects against cerebral cortical venous ischemia with suppression of apoptosis associated with inhibition of Bax expression but has little influence on regional CBF.

Does Pentraxin-3 contribute to the reduction of low-density lipoprotein levels by statin therapy?

Statins have been shown to decrease inflammatory markers, especially high sensitivity C reactive protein (hsCRP), in a dose-dependent manner. Pentraxin-3 (PTX3) is another important inflammatory biomarker from the pentraxin family that provides useful prognostic information and facilitates diagnostics of cardiovascular diseases. This study investigated the effect of statin therapy on PTX3 and hsCRP concentrations and whether statins acted synergistically with PTX3 and hsCRP concentrations in lowering LDL-C. The study group consisted of 90 patients undergoing coronary angiography. The results showed that statins reduced PTX3 concentrations (p=0.031). PTX3 and hsCRP levels were significantly different between subclinical and severe stenosis groups (p=0.011 and p=0.009, respectively). Statin therapy was significantly associated with lower PTX3 and LDL-C levels in multiple logistic analyses. The probability that statin therapy would achieve target LDL-C values was highest in patients with low PTX3 values (OR=3.683, p=0.040), while multiplicative interaction was 23.3. The effect of statins on PTX3 reduction was higher than on hsCRP. It can be suggested that statin therapy was more successful in patients with low PTX3 values.

Brief Report: Statin Effects on Myocardial Fibrosis Markers in People Living With HIV

BACKGROUND

In observational studies, patients with HIV have higher levels of soluble ST2 (sST2), galectin-3, and growth differentiation factor-15 (GDF-15) than non-HIV controls. As statins exert pleiotropic immunomodulatory effects that may affect markers of myocardial fibrosis, the objective of the current study is to determine whether biomarkers of myocardial fibrosis reflecting subclinical pathology may be modified by statin therapy in patients with HIV.

SETTING AND METHODS

Forty HIV+ men and women participated in a single center 12-month randomized, double-blind placebo-controlled trial of atorvastatin 40 mg every day vs. placebo. At baseline and 12-months, sST2, GDF-15, galectin-3 were measured.

RESULTS

The changes in sST2 were -0.310 (-4.195, 2.075) vs. 1.163 (0.624, 4.715) ng/mL, median (interquartile range) atorvastatin vs. placebo (P = 0.04). The change in sST2 was significantly related to changes in monocyte activation marker sCD14 (r = 0.63, P < 0.0001) and MCP (r = 0.52, P = 0.0009), markers of generalized inflammation hs-IL-6 (r = 0.58, P = 0.0002), oxLDL (r = 0.49, P = 0.002), and GDF-15 (r = 0.54, P = 0.0008).

CONCLUSIONS

sST2, a member of the IL-1 receptor family and a marker of fibrosis and inflammation increases over time among patients with HIV and this increase is attenuated by statin therapy in HIV. This effect may relate to immunomodulatory mechanisms of statins.

Endothelial α6β4 integrin protects during experimental autoimmune encephalomyelitis-induced neuroinflammation by maintaining vascular integrity and tight junction protein expression

Background

Extracellular matrix (ECM) proteins play critical functions regulating vascular formation and function. Laminin is a major component of the vascular basal lamina, and transgenic mice deficient in astrocyte or pericyte laminin show defective blood-brain barrier (BBB) integrity, indicating an important instructive role for laminin in cerebral blood vessels. As previous work shows that in the normal brain, vascular expression of the laminin receptor α6β4 integrin is predominantly restricted to arterioles, but induced on all vessels during neuroinflammation, it is important to define the role of this integrin in the maintenance of BBB integrity.

Methods

α6β4 integrin expression was analyzed using dual immunofluorescence (dual-IF) of brain sections taken from the mouse model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). To investigate the role of endothelial α6β4 integrin, transgenic mice lacking β4 integrin in endothelial cells (β4-EC-KO) and wild-type (WT) littermates were subject to EAE, and clinical score and various neuropathological parameters were examined by immunofluorescence. In addition, β4 integrin null brain endothelial cells (BECs) were examined in culture for expression of tight junction proteins using immunocytochemistry and flow cytometry.

Results

Cerebrovascular expression of β4 integrin was markedly upregulated during EAE progression, such that by the acute stage of EAE (day 21), the vast majority of blood vessels expressed β4 integrin. In the EAE model, while the β4-EC-KO mice showed the same time of disease onset as the WT littermates, they developed significantly worse clinical disease over time, resulting in increased clinical score at the peak of disease and maintained elevated thereafter. Consistent with this, the β4-EC-KO mice showed enhanced levels of leukocyte infiltration and BBB breakdown and also displayed increased loss of the endothelial tight junction proteins claudin-5 and ZO-1. Under pro-inflammatory conditions, primary cultures of β4KO BECs also showed increased loss of claudin-5 and ZO-1 expression.

Conclusions

Taken together, our data suggest that α6β4 integrin upregulation is an inducible protective mechanism that stabilizes the BBB during neuroinflammatory conditions.

Variability in statin-induced changes in gene expression profiles of pancreatic cancer

Statins, besides being powerful cholesterol-lowering drugs, also exert potent anti-proliferative activities. However, their anti-cancer efficacy differs among the individual statins. Thus, the aim of this study was to identify the biological pathways affected by individual statins in an in vitro model of human pancreatic cancer. The study was performed on a human pancreatic cancer cell line MiaPaCa-2, exposed to all commercially available statins (12 μM, 24 h exposure). DNA microarray analysis was used to determine changes in the gene expression of treated cells. Intracellular concentrations of individual statins were measured by UPLC (ultra performance liquid chromatography)-HRMS (high resolution mass spectrometer). Large differences in the gene transcription profiles of pancreatic cancer cells exposed to various statins were observed; cerivastatin, pitavastatin, and simvastatin being the most efficient modulators of expression of genes involved namely in the mevalonate pathway, cell cycle regulation, DNA replication, apoptosis and cytoskeleton signaling. Marked differences in the intracellular concentrations of individual statins in pancreatic cancer cells were found (>11 times lower concentration of rosuvastatin compared to lovastatin), which may contribute to inter-individual variability in their anti-cancer effects. In conclusion, individual statins exert different gene expression modulating effects in treated pancreatic cancer cells. These effects may be partially caused by large differences in their bioavailability. We report large differences in gene transcription profiles of pancreatic cancer cells exposed to various statins. These data correlate to some extent with the intracellular concentrations of statins, and may explain the inter-individual variability in the anti-cancer effects of statins.

Plasma Pentraxin 3 Differentiates Nonalcoholic Steatohepatitis (NASH) from Non-NASH

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) includes a variety of histopathological findings ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) which can only be differentiated by liver biopsy. There is yet no unique biomarker found to discriminate NASH from simple steatosis.We aimed to investigate the relationship of plasma pentraxin 3 (PTX3) and its main stimulant tumor necrosis factor alpha (TNF-α) with the degree of liver damage in NAFLD.

METHODS

Plasma PTX3 and TNF-α levels were measured in 70 patients with histologically verified NAFLD (56 with NASH, 14 with non-NASH) and 12 controls.

RESULTS

PTX3 and TNF-α levels were found significantly higher in the NAFLD group than in the control group (4.1 ± 2.3 vs. 1.3 ± 0.8 ng/mL, P < 0.001, and 7.6 ± 4.1 vs. 3.3 ± 1.3 pg/mL, P < 0.001 respectively) and in biopsy proven NASH subgroup than non-NASH subgroup (4.6 ± 2.2 vs. 2.2 ± 1.7 ng/mL, P = 0.001, and 8.3 ± 4.3 vs. 4.6 ± 1.6 pg/mL, P = 0.001 respectively). To discriminate NASH from non-NASH PTX3 had 91.1% sensitivity and 71.4% specificity at the cutoff value of 2.45 ng/mL. Plasma PTX3 levels showed correlation with NAFLD activity score, fibrosis stage and steatosis grade (r = 0.659, P < 0.001; r = 0.354, P < 0.01; and r = 0.455, P < 0.001, respectively).

CONCLUSION

This study demonstrated markedly higher PTX3 levels in NAFLD patients compared with controls, and in biopsy proven NASH patients compared with non-NASH ones. Thus, in this cohort we showed that plasma PTX3 may be a promising biomarker for the presence of NASH.

Atorvastatin reduces long pentraxin 3 expression in vascular cells by inhibiting protein geranylgeranylation

BACKGROUND

The long pentraxin PTX3 is an acute-phase multi-functional protein that might play both positive and detrimental effects under different pathophysiological conditions. We previously showed that statins down-regulate the release of PTX3 in human endothelial cells (ECs). The present study investigated the mechanism mediating this effect, its occurrence in other cells involved in atherogenesis, and whether it takes place in experimental atherosclerosis.

METHODS AND RESULTS

We found that atorvastatin (1-5 μmol/L) decreased the production and release of PTX3 in human ECs through a post-transcriptional effect. Co-incubation with mevalonate or geranylgeranyl pyrophosphate prevented this effect. Direct blockade of geranylgeranyl transferase I by GGTI-286, treatment with the Rac inhibitor NSC23766 or silencing of the geranylgeranylated GTPase Rac2 by siRNA closely mimicked the action of atorvastatin. In contrast, inactivation of other geranylgeranylated proteins such as RhoA, RhoB, and RhoC or Rac1 did not affect PTX3 release. In addition, we found that atorvastatin also decreased PTX3 secretion in aortic SMCs through a mechanism likely dependent on protein geranylgeranylation, while no effect was observed in monocytes. Finally, we found that atherosclerotic lesions from cholesterol-fed rabbits treated with atorvastatin (2.5 mg/kg/day for 8 weeks) showed less immunoreactive PTX3 than lesions from control animals.

CONCLUSIONS

Results suggest that statins may interfere with PTX3 expression in vascular cells via inhibition of protein geranylgeranylation. Since PTX3 is increasingly regarded as an important mediator of the inflammatory response underlying atherosclerosis and its complications, these results highlight the need for further studies of the role of PTX3 and its potential pharmacological modulation in cardiovascular disease.

Endothelial protective genes induced by statin are mimicked by ERK5 activation as triggered by a drug combination of FTI-277 and GGTI-298

BACKGROUND

Statins are potent inhibitors of cholesterol biosynthesis and are clinically beneficial in preventing cardiovascular diseases, however, the therapeutic utility of these drugs is limited by myotoxicity. Here, we explored the mechanism of statin-mediated activation of ERK5 in the human endothelium with the goal of identifying compounds that confer endothelial protection but are nontoxic to muscle.

METHODS

An ERK5-one hybrid luciferase reporter transfected into COS-7 cells with pharmacological and molecular manipulations dissected the signaling pathway leading to statin activation of ERK5. qRT-PCR of HUVEC cells documented the transcriptional activation of endothelial-protective genes. Lastly, morphological and cellular ATP analysis, and induction of atrogin-1 in C2C12 myotubes were used to assess statin-induced myopathy.

RESULTS

Statin activation of ERK5 is dependent on the cellular reduction of GGPPs. Furthermore, we found that the combination of FTI-277 (inhibitor of farnesyl transferase) and GGTI-298 (inhibitor of geranylgeranyl transferase I) mimicked the statin-mediated activation of ERK5. FTI-277 and GGTI-298 together recapitulated the beneficial effects of statins by transcriptionally upregulating anti-inflammatory mediators such as eNOS, THBD, and KLF2. Finally, C2C12 skeletal myotubes treated with both FTI-277 and GGTI-298 evoked less morphological and cellular changes recognized as biomarkers of statin-associated myopathy.

CONCLUSIONS

Statin-induced endothelial protection and myopathy are mediated by distinct metabolic intermediates and co-inhibition of farnesyl transferase and geranylgeranyl transferase I confer endothelial protection without myopathy.

GENERAL SIGNIFICANCE

The combinatorial FTI-277 and GGTI-298 drug regimen provides a promising alternative avenue for endothelial protection without myopathy.

RNA-sequencing analysis of HepG2 cells treated with atorvastatin

The cholesterol-lowering drug atorvastatin is among the most prescribed drug in the world. Alternative splicing in a number of genes has been reported to be associated with variable statin response. RNA-seq has proven to be a powerful technique for genome-wide splice variant analysis. In the present study, we sought to investigate atorvastatin responsive splice variants in HepG2 cells using RNA-seq analysis to identify novel candidate genes implicated in cholesterol homeostasis and in the statin response. HepG2 cells were treated with 10 µM atorvastatin for 24 hours. RNA-seq and exon array analyses were performed. The validation of selected genes was performed using Taqman gene expression assays. RNA-seq analysis identified 121 genes and 98 specific splice variants, of which four were minor splice variants to be differentially expressed, 11 were genes with potential changes in their splicing patterns (SYCP3, ZNF195, ZNF674, MYD88, WHSC1, KIF16B, ZNF92, AGER, FCHO1, SLC6A12 and AKAP9), and one was a gene (RAP1GAP) with differential promoter usage. The IL21R transcript was detected to be differentially expressed via RNA-seq and RT-qPCR, but not in the exon array. In conclusion, several novel candidate genes that are affected by atorvastatin treatment were identified in this study. Further studies are needed to determine the biological significance of the atorvastatin responsive splice variants that have been uniquely identified using RNA-seq.

PTX3: a modulator of human coronary plaque vulnerability acting by macrophages type 2

BACKGROUND

Acute myocardial infarction (AMI), is related to a diffuse active inflammation of the coronary tree associated with rupture of one of the multiple vulnerable plaques. The presence of soluble mediators of inflammation with their synergic or antagonistic actions coordinates the physiological response determining the plaque fate and the fatal event. The present study focus on the cytokines network operating in human coronary plaques of patients died from AMI and controls, pointing out that coronaries of AMI patients produce PTX3 protein twice as that of controls and express high level of PTX3 mRNA.

RESULTS

The presence of CX3CR1 polymorphisms is significantly correlated with the incidence and the outcome of acute myocardial infarction inducing in the whole coronary tree a strong recruitment of Th1 polarized inflammation that is directly correlated to PTX3 expression.

CONCLUSIONS

Moreover we found a positive correlation between the expression of PTX3 in the plaque and the content of macrophage cells showing a M2 polarization indicating the possible role of this chemokine as mediator of immune response that would orchestrate plaque evolution and inflammatory cell type activation.

Statins as regulators of redox state in the vascular endothelium: beyond lipid lowering

SIGNIFICANCE

Endothelial dysfunction and the imbalance between nitric oxide (NO) and reactive oxygen species production in the vascular endothelium are important early steps in atherogenesis, a major socioeconomic health problem. Statins have well-established roles in primary and secondary prevention of cardiovascular disease (CVD), due to both their lipid-lowering capacity and their pleiotropic properties. It is therefore important to understand the mechanisms by which statins can modify endothelial function and affect atherogenesis.

RECENT ADVANCES

In the last decade, the concept of statin pleiotropy has been reinforced by a large number of cell culture, animal, and translational studies. Statins have been shown to suppress the activity of pro-oxidant enzymes (such as NADPH oxidase) and pro-inflammatory transcriptional pathways in the endothelium. At the same time, they enhance endothelial NO synthase expression and activity while they also improve its enzymatic coupling. This leads to increased NO bioavailability and improved endothelial function.

CRITICAL ISSUES

Despite significant recent advances, the exact mechanisms of statin pleitropy are still only partially understood. The vast majority of the published literature relies on animal studies, while the actual mechanistic studies in humans are limited.

FUTURE DIRECTIONS

The success of statins as endothelium redox-modifying agents with a direct impact on clinical outcome highlights the importance of the endothelium as a therapeutic target in CVD. Better understanding of the mechanisms that underlie endothelial dysfunction could lead to the design of novel therapeutic strategies that target the vascular endothelium for the prevention and treatment of CVD.

Implications of pentraxin 3 levels in patients with acute aortic dissection

Acute aortic dissection (AAD) causes transient inflammation with occasional pleural fluid (PF) accumulation. Although pentraxin 3 (PTX3) is a vascular inflammation-related biomarker, little is known about PTX3 levels in patients with AAD. We explored the serial changes in plasma PTX3 levels and the association of peak levels with the amount of PF accumulation. Consecutive patients (n = 41) with Stanford type B AAD were enrolled, and blood samples for the measurements of serum albumin, plasma PTX3 and high-sensitivity C-reactive protein (CRP) were collected daily until 7 days after symptom onset. PF accumulation on computed tomography imaging on the third hospital day was divided into 3 grades (I: none or slight, II: mild in the uni- or bilateral pleural cavity, III: moderate or more). PTX3 and CRP levels were analyzed after logarithmic transformation because of their skewed distributions. Peak PTX3 and CRP levels were observed at 4.3 ± 2.1 and 4.7 ± 2.0 days after symptom onset, and their values were 12.2 [interquartile range (IQR), 8.2-20.9] ng/mL and 12.0 (IQR, 8.6-15.2) mg/dL, respectively. On univariate analysis, the peak level of PTX3 had a negative correlation with the minimum level of serum albumin, and a positive correlation with PF grade and duration of intensive care unit stay. On multivariate analysis, the peak level of PTX3 was correlated with PF grade (P = 0.037). In conclusion, the peak level of PTX3 in patients with AAD was associated with the amount of transient PF accumulation, which may be associated with inflammatory vascular permeability.

Pharmacogenomics in the development and characterization of atheroprotective drugs

Atherosclerosis is the main cause of cardiovascular disease (CVD) and can lead to stroke, myocardial infarction, and death. The clinically available atheroprotective drugs aim mainly at reducing the levels of circulating low-density lipoprotein (LDL), increasing high-density lipoprotein (HDL), and attenuating inflammation. However, the cardiovascular risk remains high, along with morbidity, mortality, and incidence of adverse drug events. Pharmacogenomics is increasingly contributing towards the characterization of existing atheroprotective drugs, the evaluation of novel ones, and the identification of promising, unexplored therapeutic targets, at the global molecular pathway level. This chapter presents highlights of pharmacogenomics investigations and discoveries that have contributed towards the elucidation of pharmacological atheroprotection, while opening the way to new therapeutic approaches.

Simvastatin and t-butylhydroquinone suppress KLF1 and BCL11A gene expression and additively increase fetal hemoglobin in primary human erythroid cells

Although increased fetal hemoglobin (HbF) levels have proven benefit for people with β-hemoglobinopathies, all current HbF-inducing agents have limitations. We previously reported that drugs that activate the NRF2 antioxidant response signaling pathway increase HbF in primary human erythroid cells. In an attempt to increase HbF levels achieved with NRF2 activators, in the present study, we investigated potential complementary activity between these agents and HMG-CoA reductase inhibitors (statins) based on their ability to induce KLF2 protein levels. Experiments in K562 cells showed that simvastatin increased KLF2 mRNA and protein and KLF2 binding to HS2 of the β-globin locus control region and enhanced -globin mRNA production by the NRF2 activator Tert-butylhydroquinone (tBHQ). When tested in differentiating primary human erythroid cells, simvastatin induced HbF alone and additively with tBHQ, but it did not increase KLF2 mRNA or locus control region binding above levels seen with normal differentiation. Investigating alternative mechanisms of action, we found that both simvastatin and tBHQ suppress β-globin mRNA and KLF1 and BCL11A mRNA and protein, similar to what is seen in people with an HPFH phenotype because of KLF1 haploinsufficiency. These findings identify statins as a potential class of HbF-inducing agents and suggest a novel mechanism of action based on pharmacologic suppression of KLF1 and BCL11A gene expression.

KEY POINTS

Simvastatin and tBHQ suppress KLF1 and BCL11 gene expression and additively increase fetal hemoglobin in primary human erythroid cells. Because both drugs are FDA-approved, these findings could lead to clinical trials in the relatively near future.

Pleiotropic effects of pitavastatin

3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) are established first line treatments for hypercholesterolaemia. In addition to the direct effects of statins in reducing concentrations of atherogenic low density lipoprotein cholesterol (LDL-C), several studies have indicated that the beneficial effects of statins may be due to some of their cholesterol-independent, multiple (pleiotropic) effects which may differ between different members of the class. Pitavastatin is a novel synthetic lipophilic statin that has a number of pharmacodynamic and pharmacokinetic properties distinct from those of other statins, which may underlie its potential pleiotropic benefits in reducing cardiovascular risk factors. This review examines the principal pleiotropic effects of pitavastatin on endothelial function, vascular inflammation, oxidative stress and thrombosis. The article is based on a systematic literature search carried out in December 2010, together with more recent relevant publications where appropriate. The available data from clinical trials and in vitro and animal studies suggest that pitavastatin is not only effective in reducing LDL-C and triglycerides, but also has a range of other effects. These include increasing high density lipoprotein cholesterol, decreasing markers of platelet activation, improving cardiac, renal and endothelial function, and reducing endothelial stress, lipoprotein oxidation and, ultimately, improving the signs and symptoms of atherosclerosis. It is concluded that the diverse pleiotropic actions of pitavastatin may contribute to reducing cardiovascular morbidity and mortality beyond that achieved through LDL-C reduction.

Pentraxin-3 in chronic heart failure: the CORONA and GISSI-HF trials

AIMS

Pentraxin-3 (PTX3) is a component of the humoral arm of innate immunity which can regulate inflammatory processes. Since the role of inflammation in the progression of chronic heart failure (HF) is debated, we investigated the prognostic value of PTX3 and the effect of a statin in two large populations of patients with HF.

METHODS AND RESULTS

Plasma levels of PTX3 were measured at randomization and after 3 months in 1457 patients enrolled in the Controlled Rosuvastatin Multinational Trial in HF (CORONA) and 1233 patients enrolled in the GISSI-Heart Failure trial (GISSI-HF). The relationships between baseline PTX3 levels or their changes over time and mortality were evaluated with multivariable Cox proportional hazard models including clinical factors, high sensitivity C-reactive protein (hsCRP), and N-terminal pro brain natriuretic peptide (NT-proBNP). PTX3 concentration [median (Q1-Q3) = 5.34 (3.55-7.64) ng/mL, n = 2690] was higher in females, in older patients, and those with lower body mass index. Baseline elevated PTX3 was associated with a higher risk of all-cause mortality [759 events, hazard ratio (HR) for 1 SD increase 1.20, 95% confidence interval (CI) 1.12-1.30, P < 0.0001], cardiovascular mortality (587 events, HR 1.27, 95% CI 1.17-1.38, P < 0.0001), or hospitalization for worsening HF (720 events, HR 1.21, 95% CI 1.12-1.30, P < 0.0001), and marginally improved discrimination. Three-month changes in PTX3 were associated with fatal events after adjustment for hsCRP or NT-proBNP. Rosuvastatin lowered hsCRP levels but significantly raised PTX3.

CONCLUSION

In two independent clinical trials that enrolled patients with chronic HF, PTX3 was consistently associated with outcomes. The opposite effects of a statin on hsCRP and PTX3 call for further investigation.

TRIAL REGISTRATION

NCT00336336 (GISSI-HF), NCT00206310 (CORONA).

Critical role for integrin-β4 in the attenuation of murine acute lung injury by simvastatin

The statins are a class of 3-hydroxy-3-methylglutaryl-coenzyme A-reductase inhibitors that are recognized to have pleiotropic properties. We previously reported the attenuation of LPS-induced murine acute lung injury (ALI) by simvastatin in vivo and identified relevant effects of simvastatin on endothelial cell (EC) signaling, activation, and barrier function in vitro. In particular, simvastatin induces the upregulation of integrin-β4, which in turn inhibits EC inflammatory responses via attenuation of MAPK signaling. The role of integrin-β4 in murine ALI protection by simvastatin, however, is unknown. We initially confirmed a time- and dose-dependent effect of simvastatin on increased integrin-β4 mRNA expression in human lung EC with peak protein expression evident at 16 h. Subsequently, reciprocal immunoprecipitation demonstrated an attenuation of LPS-induced integrin-β4 tyrosine phosphorylation by simvastatin (5 μM, 16 h). Increased expression of EC inflammatory cytokines [IL-6, IL-8, monocyte chemoattractant protein (MCP)-1, regulated on activation normal T cell expressed and secreted (RANTES)] by LPS (500 ng/ml, 4 h) was also significantly attenuated by simvastatin pretreatment (5 μM, 16 h), but this effect was reversed by cotreatment with an integrin-β4-blocking antibody. Finally, although simvastatin (20 mg/kg) conferred significant protection in murine ALI as evidenced by decreased bronchoalveolar lavage fluid cell counts, protein, inflammatory cytokines (IL-6, IL-1β, MCP-1, RANTES), decreased Evans blue dye albumin extravasation in lung tissue, and changes on lung histology, these effects were reversed by the integrin-β4-blocking antibody (IV, 1 mg/kg, 2 h before LPS). These findings support integrin-β4 as an important mediator of ALI protection by simvastatin and implicate signaling by integrin-β4 as a novel therapeutic target in patients with ALI.

Are all statins the same? Focus on the efficacy and tolerability of pitavastatin

Pitavastatin is the newest member of the HMG-CoA reductase inhibitor family and is approved as adjunctive therapy to diet to reduce elevated levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, apolipoprotein (Apo) B, and triglycerides and to increase levels of high-density lipoprotein (HDL) cholesterol in adult patients with primary hyperlipidemia or mixed dyslipidemia. Pitavastatin undergoes minimal metabolism by cytochrome P450 (CYP) enzymes and, therefore, has a low propensity for drug-drug interactions with drugs metabolized by CYP enzymes or the CYP3A4 substrate grapefruit juice. In clinical trials, pitavastatin potently and consistently reduced serum levels of total, LDL, and non-HDL cholesterol, and triglycerides in patients with primary hypercholesterolemia where diet and other non-pharmacological measures were inadequate. Mean reductions from baseline in serum total and LDL cholesterol and triglyceride levels were 21-32%, 30-45%, and 10-30%, respectively. Moreover, a consistent trend towards increased HDL cholesterol levels of 3-10% was seen. Long-term extension studies show that the beneficial effects of pitavastatin are maintained for up to 2 years. Pitavastatin produces reductions from baseline in serum total and LDL cholesterol levels to a similar extent to those seen with the potent agent atorvastatin and to a greater extent than those seen with simvastatin or pravastatin. In the majority of other studies comparing pitavastatin and atorvastatin, no significant differences in the favorable effects on lipid parameters were seen, although pitavastatin was consistently associated with trends towards increased HDL cholesterol levels. Pitavastatin also produces beneficial effects on lipids in patients with type 2 diabetes mellitus and metabolic syndrome without deleterious effects on markers of glucose metabolism, such as fasting blood glucose levels or proportion of glycosylated hemoglobin. Pitavastatin appears to exert a number of beneficial effects on patients at risk of cardiovascular events independent of lipid lowering. In the JAPAN-ACS (Japan Assessment of Pitavastatin and Atorvastatin in Acute Coronary Syndrome) study, pitavastatin was non-inferior to atorvastatin at reducing plaque volume in patients with ACS undergoing percutaneous coronary intervention. Further beneficial effects, including favorable effects on the size and composition of atherosclerotic plaques, improvements in cardiovascular function, and improvements in markers of inflammation, oxidative stress, and renal function, have been demonstrated in a number of small studies. Pitavastatin is generally well tolerated in hyperlipidemic patients with or without type 2 diabetes, with the most common treatment-related adverse events being musculoskeletal or gastrointestinal in nature. Increases in plasma creatine kinase levels were seen in <5% of pitavastatin recipients and the incidence of myopathy or rhabdomyolysis was extremely low. In summary, pitavastatin, the latest addition to the statin family, produces potent and consistent beneficial effects on lipids, is well tolerated, and has a favorable pharmacokinetic profile. The combination of a potent decrease in total and LDL cholesterol levels and increase in HDL cholesterol levels suggest that pitavastatin may produce substantial cardiovascular protection.

The Use of High-Throughput Technologies to Investigate Vascular Inflammation and Atherosclerosis

The greatest challenge of scientific research is to understand the causes and consequences of disease. In recent years, great efforts have been devoted to unraveling the basic mechanisms of atherosclerosis (the underlying pathology of cardiovascular disease), which remains a major cause of morbidity and mortality worldwide. Because of the complex and multifactorial pathophysiology of cardiovascular disease, different research techniques have increasingly been combined to unravel genetic aspects, molecular pathways, and cellular functions involved in atherogenesis, vascular inflammation, and dyslipidemia to gain a multifaceted picture addressing this complexity. Thanks to the rapid evolution of high-throughput technologies, we are now able to generate large-scale data on the DNA, RNA, and protein levels. With the help of sophisticated computational tools, these data sets are integrated to enhance information extraction and are being increasingly used in a systems biology approach to model biological processes as interconnected and regulated networks. This review exemplifies the use of high-throughput technologies—such as genomics, transcriptomics, proteomics, and epigenomics—and systems biology to explore pathomechanisms of vascular inflammation and atherosclerosis.

Pentraxin 3: a novel biomarker for inflammatory cardiovascular disease

Numerous studies have recently examined the role of pentraxin 3 (PTX3) in clinical situations. The pentraxin family includes C-reactive protein (CRP); however, unlike CRP, PTX3 is expressed predominantly in atherosclerotic lesions that involve macrophages, neutrophils, dendritic cells, or smooth muscle cells. Interestingly, PTX3 gene expression in human endothelial cells is suppressed to a greater extent by pitavastatin than the expression of 6,000 other human genes that have been examined, suggesting that PTX3 may be a novel biomarker for inflammatory cardiovascular disease. The expression and involvement of PTX3 in cardiovascular diseases are discussed in this paper, along with the characteristics of PTX3 that make it a suitable biomarker; namely, that the physiological concentration is known and it is independent of other risk factors. The results discussed in this paper suggest that further investigations into the potential novel use of PTX3 as a biomarker for inflammatory cardiovascular disease should be undertaken.

Differential effect of atorvastatin and tacrolimus on proliferation of vascular smooth muscle and endothelial cells

Although considered promising for use in drug-eluting stents (DES), tacrolimus failed clinically. Tacrolimus inhibits growth factor production but can also act as a growth factor on vascular smooth muscle cells (VSMC). This unexpected proliferative stimulus could reverse the beneficial effects of the drug on restenosis. We hypothesized that tacrolimus' association with statins, which lower cholesterol and impair cell proliferation, could restore tacrolimus' beneficial effect by abrogating the aberrant proliferative stimulus. Additionally, since maintenance of endothelial function represents a challenge for new-generation DES, we investigated the combined effect of tacrolimus and atorvastatin on endothelial cells. Human VSMC and umbilical vein endothelial cells (HUVEC) were incubated with 100 nM tacrolimus and increasing doses of atorvastatin (0-3.0 μM). Atorvastatin plus tacrolimus dose-dependently inhibited VSMC proliferation. The percentage of cells incorporating 5-bromo-2'-deoxyuridine (BrdU) in their DNA was 49 ± 14% under basal conditions, 62 ± 15% (P = 0.01) with tacrolimus, 40 ± 22% with 3 μM atorvastatin, and 30 ± 7% (P < 0.05) with 3 μM atorvastatin plus tacrolimus. Atorvastatin downregulated β-catenin, Erk1 and Erk2, and cyclin B in tacrolimus-stimulated VSMC. In contrast, atorvastatin plus tacrolimus did not affect proliferation of endothelial cells. The percentage of HUVEC incorporating BrdU in their DNA was 47 ± 8% under basal conditions, 58 ± 6% (P = 0.01) with tacrolimus, 45 ± 4% with 3 μM atorvastatin, and 49 ± 1% with 3 μM atorvastatin plus tacrolimus. Both agents stimulated endoglin production by HUVEC. Taken together, these results suggest that, when combined with tacrolimus, atorvastatin exerts a dose-dependent antiproliferative effect on VSMC. In contrast, atorvastatin acts in concert with tacrolimus in HUVEC to stimulate production of endoglin, a factor that has an important role in endothelial repair. Our study supports the conclusion that prevention of postcoronary in-stent restenosis and late thrombosis may benefit of concomitant association of tacrolimus and high doses of atorvastatin.

Pitavastatin: finding its place in therapy

Dyslipidaemia is a major risk factor for cardiovascular (CV) disease. Despite the widespread availability of effective lipid-lowering agents, an unacceptably large proportion of patients fail to attain their target low-density lipoprotein cholesterol (LDL-C) level in clinical practice. Reasons for this include undertreatment, poor adherence/persistence with therapy and failure to address non-LDL-C residual risk factors such as high levels of triglycerides, low high-density lipoprotein cholesterol (HDL-C) concentrations and raised apolipoprotein B: apolipoprotein A1 ratios. Pitavastatin is a novel, well-tolerated statin with a noninferior or superior lipid-lowering efficacy to comparable doses of atorvastatin, simvastatin, and prava-statin in a wide range of patients with hypercholesterolemia or combined dyslipidaemia. Compared with other statins, pitavastatin produces consistently greater increases in HDL-C levels that are sustained over the long term. In addition to pravastatin's potent effects on lipid profiles, a number of pleiotropic benefits have been identified that may contribute to a reduction in residual cardiovascular risk in people with dyslipidaemia and could partly account for pitavastatin's ability to regress coronary plaques in patients with acute coronary syndrome. Pitavastatin's unique metabolic profile results in a high efficacy at low (1-4 mg) doses and minimal drug interactions with cytochrome CYP3A4 substrates, making it an excellent choice for people requiring multiple medications. Although future trials are required to assess the impact of pitavastatin treatment on CV morbidity and mortality, studies to date suggest that pitavastatin will play an important role in the future management of dyslipidaemia and in the overall reduction of CV risk.

HuR regulates the expression of stress-sensitive genes and mediates inflammatory response in human umbilical vein endothelial cells

An important aspect of vascular biology is the identification of regulators of stress-sensitive genes that play critical roles in mediating inflammatory response. Here, we show that expression of HuR in human umbilical vein endothelial cells is regulated by shear stress and statin treatment; HuR, in turn, regulates other stress-sensitive genes such as Kruppel-like factor 2 (Klf2), endothelial nitric oxide synthase (eNOS), and bone morphogenic protein 4 (BMP-4). We found that siRNA knockdown of HuR-inhibited inflammatory responses in endothelial cells, including ICAM-1 and VCAM-1 up-regulation, NFkappaB phosphorylation, and adhesion of monocytes. Tissue staining of the mouse aorta revealed increased HuR expression in the lesser curvature region of the arch that is exposed to disturbed flow, consistent with our in vitro data. Taken together, these results suggest that HuR plays a critical role in inducing inflammatory response of endothelial cells under mechanical and biochemical stresses.

Critical appraisal of the role of pitavastatin in treating dyslipidemias and achieving lipid goals

Pitavastatin is a potent HMG-CoA reductase inhibitor and efficient hepatocyte low-density lipoprotein cholesterol (LDL-C) receptor inducer, producing robust reduction of the serum LDL-C levels, even at a low dose. Pitavastatin and its lactone form are minimally metabolized by CYP enzymes, and are therefore associated with minimal drug-drug interactions (DDIs). Pitavastatin 2 to 4 mg has potent LDL-C-reducing activity, equivalent to that of atorvastatin 10 to 20 mg; several clinical trials have revealed consistently superior high-density lipoprotein cholesterol (HDL-C) elevating activity of pitavastatin than that of atorvastatin. Pitavastatin-induced HDL-C elevation has been shown to be sustained, even incremental, in long-term clinical trials. Pitavastatin was as well-tolerated as atorvastatin or simvastatin in double-blind randomized clinical trials. Two-year long-term safety and effectiveness of pitavastain has been confirmed in a large-scale, prospective post-marketing surveillance. The safety and efficacy profile of pitavastatin is favorable for the treatment of dyslipidemia, especially in metabolic syndrome patients. In addition to control of LDL-C, adequate control of triglyceride (TG) and HDL-C, hypertension and hyperglycemia is also necessary in metabolic syndrome patients. Pitavastatin produces adequate control of LDL-C and TG, along with potent and incremental HDL-C elevation, with a low frequency of DDIs.

Gene expression patterns in peripheral blood correlate with the extent of coronary artery disease

Systemic and local inflammation plays a prominent role in the pathogenesis of atherosclerotic coronary artery disease, but the relationship of whole blood gene expression changes with coronary disease remains unclear. We have investigated whether gene expression patterns in peripheral blood correlate with the severity of coronary disease and whether these patterns correlate with the extent of atherosclerosis in the vascular wall.

Patients were selected according to their coronary artery disease index (CADi), a validated angiographical measure of the extent of coronary atherosclerosis that correlates with outcome. RNA was extracted from blood of 120 patients with at least a stenosis greater than 50% (CADi≥23) and from 121 controls without evidence of coronary stenosis (CADi = 0).

160 individual genes were found to correlate with CADi (rho>0.2, P<0.003). Prominent differential expression was observed especially in genes involved in cell growth, apoptosis and inflammation. Using these 160 genes, a partial least squares multivariate regression model resulted in a highly predictive model (r² = 0.776, P<0.0001). The expression pattern of these 160 genes in aortic tissue also predicted the severity of atherosclerosis in human aortas, showing that peripheral blood gene expression associated with coronary atherosclerosis mirrors gene expression changes in atherosclerotic arteries.

In conclusion, the simultaneous expression pattern of 160 genes in whole blood correlates with the severity of coronary artery disease and mirrors expression changes in the atherosclerotic vascular wall.

Effects of atorvastatin on angiogenesis in hindlimb ischemia and endothelial progenitor cell formation in rats

AIM

To investigate the mechanisms underlying the pro-angiogenic effects of statin, the effects of atorvastatin were investigated on the expression of angiogenic factors in ischemic hindlimbs of rats. The function and number of endothelial progenitor cells (EPCs) were investigated in hypertensive rats.

METHODS

Hindlimb ischemia rats were administered 10 or 30 mg/kg/day atorvastatin orally for 2 weeks. Angiogenesis was evaluated by a laser Doppler and by Isolectin-B4 immunostaining. The expressions of VEGF, IL-8, angiopoietin (Ang)-1, Ang-2, eNOS, and hemoxidase (HO)-1 were evaluated by Western blotting and immunohistochemistry. Spontaneously hypertensive rats (SHR) were administered 10 mg/kg/day atorvastatin. EPC function was evaluated by colony formation and migration. The EPC number was evaluated by CD34-positive cells.

RESULTS

A lowdose of atorvastatin, but not a highdose, significantly increased regional blood flow. Atorvastatin significantly increased the expressions of VEGF, IL-8, Ang-1, Ang-2, eNOS, and HO-1 proteins in ischemic hindlimbs. Atorvastatin significantly increased the number and colony formation of EPCs and decreased oxidation in mononuclear cells from SHR.

CONCLUSION

Atorvastatin strongly induced angiogenesis with increases in angiogenic cytokines, HO-1 and EPC numbers. Statins are thus considered potertial agents for therapeutic angiogenesis.

The influence of lovastatin on thrombomodulin gene expression in vascular endothelial cells--in vitro study

OBJECTIVE

Statins reduce lipids concentration in blood. The latest investigations show they also improved the function of vascular endothelial cells (ECs). Thrombomodulin (TM) is particularly important marker of ECs activity. We investigated the in vitro effect of lovastatin on the expression level of TM gene.

METHODS AND RESULTS

ECs were incubated for 24 h in culture medium including lovastatin in 3 concentrations: 0.1, 1.0, 10.0 mol/l. The mRNA level of TM increased in correlation with rising concentrations of lovastatin to 600 % vs. control group.

CONCLUSIONS

TM is essential antithrombotic factor in endothelial cells. Lovastatin significantly raises thrombomodulin gene expression. It is important characteristics of this medicine, which prevents cardiovascular events.

Plasma Pentraxin3 is a novel marker for nonalcoholic steatohepatitis (NASH)

Background

The changes in the liver in nonalcoholic fatty liver disease (NAFLD) range over a wide spectrum, extending from steatosis to steatohepatitis (NASH). However it has remained difficult to differentiate between NASH and non-progressive NAFLD on the basis of the clinical findings alone.

Aims

In this study we investigated the clinical usefulness of plasma Pentraxin3 (PTX3) levels to predict NASH. Plasma PTX3 was measured in 70 patients with histologically verified NAFLD (28 with non-NASH and 42 with NASH) and 10 healthy control subjects.

Results

The plasma PTX3 level was significantly higher in the NASH cases than in the non-NASH cases (p = 0.0021) and control subjects (p = 0.045). And the plasma PTX3 level was significantly higher in the stages 3–4 NAFLD cases than in the stages 0–2 NAFLD cases (p < 0.0001). The PTX3 values were closely correlated with the stages of liver fibrosis (p < 0.0001, Kruskal-Wallis test). To detect NASH compared with non-NASH, the area under the curve for plasma PTX3 were 0.755, and to detect stages 3–4 NAFLD compared with stages 0–2 NAFLD, the area under the curve for plasma PTX3 were 0.850.

Conclusion

This is the first study to demonstrate consistent and profound elevation of plasma PTX3 levels in NASH in comparison with non-NASH. The results suggest that plasma PTX3 levels may not only be laboratory values that differentiate NASH from non-NASH, but marker of the severity of hepatic fibrosis in NASH.

Comparative gene expression profiling in three primary human cell lines after treatment with a novel inhibitor of Rho kinase or atorvastatin

Inhibitors of Rho kinase (ROCK) are a relatively new class of drugs with potential benefits in oncology, neurology, and fibrotic and cardiovascular diseases. ROCK inhibitors modulate many cellular functions, some of which are similar to the pleiotropic effects of statins, suggesting additive or synergistic properties. Studies to date have used compounds that inhibit both isoforms of ROCK, ROCK1 and ROCK2. This study was designed to compare gene expression profiles of atorvastatin with the newly developed ROCK2 inhibitor SLx-2119 in primary cultures of normal human endothelial cells, smooth muscle cells, and fibroblasts. Cells were treated with each compound for 24 h, after which total RNA was isolated and genome-wide gene-expression profiles were obtained with Illumina arrays. Because of the known effect of statins on the actin cytoskeleton and on connective tissue growth factor, a prominent growth factor involved in tissue fibrosis, the effects of SLx-2119 and atorvastatin on the actin cytoskeleton and connective tissue growth factor mRNA were also examined in cultures of smooth muscle cells with a fibrotic phenotype, isolated from biopsies of human intestine with radiation-induced fibrosis. Although SLx-2119 and atorvastatin affected expression of genes belonging to the same biological processes, individual genes were mostly different, consistent with synergistic or additive properties. Both SLx-2119 and atorvastatin reduced connective tissue growth factor mRNA and remodeled the actin cytoskeleton in fibrosis-derived smooth muscle cells, suggesting that both compounds have antifibrotic properties. These results form the basis for further studies to assess the possible therapeutic benefit of combined treatments.

Rosuvastatin regulates vascular smooth muscle cell phenotypic modulation in vascular remodeling: Role for the urokinase receptor

The urokinase (uPA)/urokinase receptor (uPAR) multifunctional system is an important mediator of migration and proliferation of vascular smooth muscle cells (VSMC). However, whether uPA/uPAR-directed mechanisms are involved in the beneficial effects of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors on vascular remodeling remains unexplored. In this study, we have investigated the effect of the hydrophilic statin rosuvastatin on neointimal remodeling, and the role of uPAR. Using an ex vivo organ and in vitro cell culture models we demonstrate that rosuvastatin decreases injury-induced neointima formation and proliferation of medial VSMC in porcine coronary arteries, as well as migration and proliferation of human coronary VSMC. Studies on the underlying mechanisms show that rosuvastatin impairs VSMC transition from their physiological contractile to the pathophysiological synthetic phenotype. These effects are mediated, at least in part, via uPAR, as confirmed by means of rosuvastatin-directed uPAR expression and uPAR silencing in both models. Our findings provide evidence that rosuvastatin modulates VSMC phenotypic changes and subsequently their proliferation and migration, and indicate the important role for uPAR in these processes. This mechanism contributes to the beneficial non-lipid lowering effect of rosuvastatin on negative vascular remodeling.

Prognostic value of pentraxin 3 in patients with chronic heart failure

BACKGROUND

A long pentraxin, PTX3, is produced by vascular cells or inflammatory cells and released into the circulation, possibly reflecting local inflammation in the cardiovascular system.

AIM

This study was designed to assess the clinical significance of plasma pentraxin 3 (PTX3) levels in chronic heart failure (CHF).

METHODS

We measured plasma PTX3 levels in 37 patients with non-ischemic CHF (dilated cardiomyopathy) using enzyme-linked immunosorbent assay (ELISA) methods.

RESULTS

The plasma PTX3 levels were higher in CHF patients than in healthy subjects (P=0.001), and the CHF patients in the highest tertile of plasma PTX3 levels had more cardiac events than the patients in the lowest tertile (42% vs. 0%, P=0.02). Multivariate regression analysis showed that PTX3 was the most significant predictor of cardiac events (hazard ratio 1.912 for each increase in PTX3 of 1 ng/ml, P=0.019, 95% CI 1.114-3.282). In addition, PTX3 was strikingly expressed in human myocardial cells obtained from a biopsy specimen in a patient.

CONCLUSION

Plasma PTX3 levels might be a potentially useful biomarker to predict prognosis as well as to detect inflammatory status in patients with CHF.

Role of the soluble pattern recognition receptor PTX3 in vascular biology

Pentraxins act as soluble pattern recognition receptors with a wide range of functions in various pathophysiological conditions. The long-pentraxin PTX3 shares the C-terminal pentraxin-domain with short-pentraxins C-reactive protein and serum amyloid P component and possesses an unique N-terminal domain. These structural features suggest that PTX3 may have both overlapping and distinct biological/ligand recognition properties when compared to short-pentraxins. PTX3 serves as a mechanism of amplification of inflammation and innate immunity. Indeed, vessel wall elements produce high amounts of PTX3 during inflammation and the levels of circulating PTX3 increase in several pathological conditions affecting the cardiovascular system. PTX3 exists as a free or extracellular matrix-associated molecule and it binds the complement fraction C1q. PTX3 binds also apoptotic cells and selected pathogens, playing a role in innate immunity processes. In endothelial cells and macrophages, PTX3 upregulates tissue factor expression, suggesting its action as a regulator of endothelium during thrombogenesis and ischaemic vascular disease. Finally, PTX3 binds the angiogenic fibroblast growth factor-2, thus inhibiting its biological activity. Taken together, these properties point to a role for PTX3 during vascular damage, angiogenesis, atherosclerosis, and restenosis.

Effect of HMGCoA reductase inhibitors on cytochrome P450 expression in endothelial cell line

Endothelial cells and smooth muscle cells are the major cells that constitute blood vessels, and endothelial cells line the lumen of blood vessels. These 2 types of cells also play an integral role in the regional specialization of vascular structure. On the basis of these observations, we designed our study to investigate the effect of various statins on CYP expression in endothelial cells. 3-hydroxymethyl coenzyme A reductase inhibitors play an important role in vascular function. The majority of the statins available on the market show extensive metabolism by cytochrome P450 (CYP) enzymes. Both cell types are involved in the bioconversion of arachidonic acid into vasoactive compounds. The aim of this study was to demonstrate the effect of statins on cytochrome P450 expression in endothelial cells. Our results show that endothelial cells expressed both CYPs involved in epoxyeicosatrienoic acids (EETs) and hydroxyeicosatetraenoic acids (HETEs) production and the nuclear receptor implicated in cytochrome P450 regulation. Treatment of endothelial cells with lovastatin increased CYP2C9 expression. After 96 hours of treatment, fluvastatin and lovastatin clearly increased CYP2C9 protein level. CAR but not PXR was expressed in endothelial cells, indicating that the upregulating effect of statins on CYP2C9 in endothelial cells could be mediated through CAR only due to the lack of expression of PXR in these cells.

Effect of atorvastatin on energy expenditure and skeletal muscle oxidative metabolism at rest and during exercise

Statins are associated with adverse effects in skeletal muscle. This study tested the hypothesis that atorvastatin would increase the respiratory exchange ratio (RER) at rest and during exercise. Twenty-eight healthy subjects (mean age 52 years) were enrolled in a double-blind, placebo-controlled, randomized study of the effects of atorvastatin (40 mg/day) on whole body energetics over 8 weeks. Ventilatory gas exchange measurements, at rest and during bicycle ergometry, were used to assess muscle oxidative metabolism. Thirteen subjects from each treatment arm completed the study. Eight weeks of atorvastatin lowered plasma low-density lipoprotein cholesterol concentration but had no effect on resting or submaximal energy expenditure, RER, or calculated fatty acid oxidation rates. Atorvastatin did not affect maximal exercise oxygen consumption or the anaerobic threshold. Eight weeks of atorvastatin therapy was not associated with alterations in substrate oxidation, or muscle oxidative function at rest, or during exercise in healthy adults.

The effect of statin on the aortic gene expression profiling

BACKGROUND

Beyond lipid lowering, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) has been found to have anti-inflammatory and anti-thrombotic effects. However, the genetic expression pattern changes in atherosclerotic lesions produced by statin are rarely studied.

METHODS

Cholesterol-fed apolipoprotein (Apo) E-deficient mice were examined for the treatment effect of statin on aortic gene expression. ApoE-deficient mice were fed with a hypercholesterolemic diet started at 8 weeks of age for a total of 22 weeks. In the statin treatment group (n=25), the ApoE-deficient mice were treated with pravastatin (80 mg/kg/day) dissolved in water by daily oral inoculation from 25 to 30 weeks of age. For the control group (n=25), the ApoE-deficient mice were orally inoculated with water only for the same period of time. The aortic gene expression affected by pravastatin was identified using oligonucleotide microarray technology with Agilent gene chips.

RESULTS

The total cholesterol and atherosclerotic lesion/total aortic area were significantly lower in the pravastatin treatment group. Microarray analysis of the expression of 20,281 murine genes in the aortas between the two groups indicated that 94 genes were significantly regulated. Thirty genes were up-regulated and 64 genes were down-regulated. The most up-regulated genes were troponin T3, actin alpha1, tubulin alpha1, regulator of G-protein signaling 5 (Rgs5), stathmin-like 2 and myosin light chain kinase. Most of them are related with cytoskeleton organization, while Rgs5 is a G-protein signal transduction molecule. The most down-regulated genes were adenosine deaminase, atrial natriuretic peptide, troponin T2, FXYD domain-containing ion transport regulator 3, and glutathione S-transferase alpha4.

CONCLUSIONS

The beneficial effect of the 6-week statin treatment in ApoE-deficient mice is largely dependent on its influence on the cytoskeleton organization. Our study results might provide insight into the clinical benefits of chronic statin treatment.

Comparative expression profiling in primary and immortalized endothelial cells: changes in gene expression in response to hydroxy methylglutaryl-coenzyme A reductase inhibition

Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as well as after treatment with atorvastatin. It is necessary, however, to carefully select and validate changes in genes that are the focus of studies when using EA.hy926 cells. While this cell line is highly useful in studies on some genes, including genes encoding molecules involved in regulating thrombohemorrhagic homeostasis, they appear to be less suited for studies focused on other genes, particularly those involved in the regulation of cell proliferation and apoptosis.

Nontoxic proteasome inhibition activates a protective antioxidant defense response in endothelial cells

Inhibitors of the ubiquitin-proteasome system offer a new and promising approach in the therapy of proliferative and inflammatory diseases. In order to narrow the therapeutic window for cytotoxic effects on the one hand and nontoxic, anti-inflammatory effects on the other hand, we elucidated the complex cellular effects of toxic versus nontoxic proteasome inhibition in human endothelial cells by expressional profiling. Nontoxic doses of proteasome inhibitors induced a defined, dose-dependent transcriptional response that was markedly attenuated in terms of gene number and amplitude of regulation compared to toxic doses. In particular, we observed uniform upregulation of several antioxidative enzymes and differential regulation of genes involved in endothelial function. This adaptive transcriptional pattern was translated into a protective response of endothelial cells against H(2)O(2)-induced oxidative stress and into improvement of endothelial function of rat aortic rings. Our data thus suggest that nontoxic proteasome inhibition might offer a new therapeutic approach for the treatment of endothelial dysfunction in cardiovascular disorders.

Anti-Inflammatory Effects of Statins: Clinical Evidence and Basic Mechanisms

Chronic inflammation is a key feature of vascular disease states such as atherosclerosis. Multiple clinical studies have shown that a class of medications termed statins lower cardiovascular morbidity and mortality. Originally developed to lower serum cholesterol, increasing evidence suggests that these medications have potent anti-inflammatory effects that contribute to their beneficial effects in patients. Here, we discuss the clinical and experimental evidence underlying the anti-inflammatory effects of these agents.

Analysis of the global RNA expression profiles of skeletal muscle cells treated with statins

The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are the most effective drugs for hypercholesteloremia. However, a significant side effect of statin treatment is rhabdomyolysis. In order to study the effect of statins in skeletal muscle cells, we used a DNA microarray analysis to investigate the changes in gene expression profiles brought about by statins in two skeletal muscle cell lines, namely, differentiated rat L6 myotubes and a human skeletal muscle cell line (hSkMC). In both cell lines, the statins (atorvastatin, cerivastatin and pitavastatin) induced the expression of four genes, which relate to cholesterol metabolism, namely, HMG-CoA synthase 1, HMG-CoA reductase, farnesyl diphosphate synthase and isopentenyl-diphosphate delta isomerase. Statin inhibited the synthesis of cholesterol at least five times more effectively in hSkMCs than in the hepatocytes. In addition, unlike in osteoblasts or coronary artery smooth muscle cells, statins upregulated the mRNA expression of cholesterol-associated enzymes in hSkMCs. These results provide basic information on skeletal muscle cells treated with statins and indicate that the cells are sensitive to the inhibition of HMG-CoA reductase, which may be related to the pathogenesis of muscle damage in statin therapy.

Kruppel-like factor 2 as a novel mediator of statin effects in endothelial cells

BACKGROUND

Although 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are known to modulate endothelial function, the transcriptional mechanisms underlying these effects are incompletely understood. We hypothesized that Lung-Kruppel-like factor (LKLF/KLF2), a novel and potent regulator of endothelial gene expression, may mediate the downstream effects of statins. Here we report that statin-induced expression of endothelial NO synthase (eNOS) and thrombomodulin is KLF2 dependent.

METHODS AND RESULTS

KLF2 mRNA was induced by treatment with multiple statins in a concentration-dependent manner. Multiple lines of evidence suggest that this induction is dependent on inhibition of the Rho pathway and requires de novo transcription. Furthermore, promoter deletion and mutational analyses suggest that mevastatin induced KLF2 promoter activity through a single myocyte enhancer factor binding site. Finally, small-interfering RNA-mediated knockdown of KLF2 strongly attenuated the ability of mevastatin to increase eNOS and thrombomodulin accumulation in endothelial cells.

CONCLUSIONS

Taken together, these observations indicate that statin-dependent induction of eNOS and thrombomodulin requires KLF2 and thereby provides a novel molecular target for modulating endothelial function in vascular disease.

Statins Exert Endothelial Atheroprotective Effects via the KLF2 Transcription Factor

3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, statins, have been shown to positively impact vascular function independent of their plasma lipid-lowering action. Several of these beneficial effects involve modulation of gene expression. Here we explored whether the transcription factor Kruppel-like factor 2 (KLF2), a biomechanically activated gene we recently identified as part of the endothelial "atheroprotective phenotype," is regulated by statins and whether this mechanism is important for the non-lipid lowering beneficial effects mediated by these drugs in endothelium. The mRNA levels of KLF2 in human umbilical vein endothelial cells increased in the presence of various statins. KLF2 induction was observed within 8 h after drug treatment and remained elevated for at least 24 h. This statin effect on KLF2 expression was reversed by addition of mevalonate and its downstream metabolite geranygeranyl pyrophosphate. Furthermore, inhibition of protein geranylgeranylation with GGTI-298 significantly induced KLF2 levels, whereas inhibition of farnesylation did not. Statin-mediated KLF2 expression was followed by the up-regulation of several of its downstream transcriptional targets. Using small interfering RNA to block KLF2 expression, we demonstrated that this transcription factor is necessary for the statin-mediated regulation of several pathophysiologically relevant genes. These results strongly implicate KLF2 as a transcriptional regulator of the statin-mediated effects in vascular endothelium and provide a novel mechanism for the well established non-lipid lowering beneficial cardiovascular effects of statins.