Direct vascular effects of HMG-CoA reductase inhibitors

Therapeutic Effects of Statins: Promising Drug for Topical and Transdermal Administration

Statins are HMG-CoA reductase inhibitors and decrease plasma low-density lipoprotein cholesterol (LDL-C) levels. They are well tolerated, and because of their LDL-C-lowering effect, they are utilized to decrease the risk of atherosclerosis and cardiovascular disease. However, statins have pleiotropic effects, including immunomodulatory, anti-inflammatory, antioxidant, and anticancer. Currently, oral administration is the only Food and Drug Administration (FDA)-approved route of administration for statins. However, other administration routes have demonstrated promising results in different pre-clinical and clinical studies. For instance, statins also seem beneficial in dermatitis, psoriasis, vitiligo, hirsutism, uremic pruritus, and graft-versus-host disease. Topically applied statins have been studied to treat seborrhea, acne, rhinophyma, and rosacea. They also have beneficial effects in contact dermatitis and wound healing in animal studies, (HIV) infection, osseointegration, porokeratosis, and some ophthalmologic diseases. Topical and transdermal application of statins is a non-invasive drug administration method that has shown significant results in bypassing the first-pass metabolism in the liver, thereby reducing possible adverse effects. This study reviews the multifaceted molecular and cellular impacts of statins, their topical and transdermal application, novel delivery systems, such as nanosystems for topical and transdermal administration and the challenges concerning this approach.

Caffeic Acid-Grafted PLGA as a Novel Material for the Design of Fluvastatin-Eluting Nanoparticles for the Prevention of Neointimal Hyperplasia

Drug-eluting nanoparticles (NPs) administered by an eluting balloon represent a novel tool to prevent restenosis after angioplasty, even if the selection of the suitable drug and biodegradable material is still a matter of debate. Herein, we provide the proof of concept of the use of a novel material obtained by combining the grafting of caffeic acid or resveratrol on a poly(lactide-co-glycolide) backbone (g-CA-PLGA or g-RV-PLGA) and the pleiotropic effects of fluvastatin chosen because of its low lipophilic profile which is challenging for the encapsulation in NPs and delivery to the artery wall cells. NPs made of such materials are biocompatible with macrophages, human smooth muscle cells (SMCs), and endothelial cells (ECs). Their cellular uptake is demonstrated and quantified by confocal microscopy using fluorescent NPs, while their distribution in the cytoplasm is verified by TEM images using NPs stained with an Ag-PVP probe appositely synthetized. g-CA-PLGA assures the best control of the FLV release from NP sizing around 180 nm and the faster SMC uptake, as demonstrated by confocal analyses. Interestingly and surprisingly, g-CA-PLGA improves the FLV efficacy to inhibit the SMC migration, without altering its effects on EC proliferation and migration. The improved trophism of NPs toward SMCs, combined with the excellent biocompatibility and low modification of the microenvironment pH upon polymer degradation, makes g-CA-PLGA a suitable material for the design of drug-eluting balloons.

Anti-arrhythmic properties of non-antiarrhythmic medications

Traditional anti-arrhythmic drugs are classified by the Vaughan-Williams classification scheme based on their mechanisms of action, which includes effects on receptors and/or ion channels. Some known anti-arrhythmic drugs do not perfectly fit into this classification scheme. Other medications/molecules with established non-anti-arrhythmic indications have shown anti-arrhythmic properties worth exploring. In this narrative review, we discuss the molecular mechanisms and evidence base for the anti-arrhythmic properties of traditional non-antiarrhythmic drugs such as inhibitors of the renin angiotensin system (RAS), statins and polyunsaturated fatty acids (PUFAs). In summary, RAS antagonists, statins and PUFAs are 'upstream target modulators' that appear to have anti-arrhythmic roles. RAS blockers prevent the downstream arrhythmogenic effects of angiotensin II - the main effector peptide of RAS - and the angiotensin type 1 receptor. Statins have pleiotropic effects including anti-inflammatory, immunomodulatory, modulation of autonomic nervous system, anti-proliferative and anti-oxidant actions which appear to underlie their anti-arrhythmic properties. PUFAs have the ability to alter ion channel function and prevent excessive accumulation of calcium ions in cardiac myocytes, which might explain their benefits in certain arrhythmic conditions. Clearly, whilst a number of anti-arrhythmic drugs exist, there is still a need for randomised trials to establish whether additional agents, including those already in clinical use, have significant anti-arrhythmic effects.

Stent coating by electrospinning with chitosan/poly-cyclodextrin based nanofibers loaded with simvastatin for restenosis prevention

The main cause of failure of angioplasty stenting is restenosis due to neointimal hyperplasia, a too high proliferation of smooth muscle cells (SMC). The local and sustained delivery of selective pleiotropic drugs to limit SMC proliferation seems to be the hopeful solution to minimize this post surgery complication. The aim of this study is to develop a stent covered by nanofibers (NFs) produced by electrospinning, loaded with simvastatin (SV), a drug commonly used for restenosis prevention. NFs were prepared from the electrospinning of a solution containing SV and a mixture of chitosan (cationic) and β-cyclodextrin (CD) polymer (anionic) which form together a polyelectrolyte complex that makes up the NFs matrix. First, the SV/CD interactions were studied by phase solubility diagram, DRX and DSC. The electrospinning process was then optimized to cover a self-expandable NiTiNOL stent and the mechanical resistance of the NFs sheath upon its introduction inside the delivery catheter was considered, using a crimper apparatus. The morphology, coating thicknesses and diameters of nanofibers were studied by scanning electron microscopy. The SV loading rates on the stents were controlled by the electrospinning time, and the presence of SV in the NFs was confirmed by FTIR. NFs stability in PBS pH 7.4 buffer could be improved after thermal post-treatment of NFs and in vitro release of SV in dynamic conditions demonstrated that the release profiles were influenced by the presence of CD polymer in NFs and by the thickness of the NFs sheath. Finally, a covered stent delivering 3 µg/mm² of SV within 6 h was obtained, whose efficiency will be investigated in a further in vivo study.

Local Application of Pyrophosphorylated Simvastatin Prevents Experimental Periodontitis

PURPOSE

Simvastatin (SIM), a HMG-CoA reductase inhibitor widely prescribed for hypercholesterolemia, has been reported to ameliorate inflammation and promote osteogenesis. Its clinical applications on these potential secondary indications, however, have been hampered by its lack of osteotropicity and poor water solubility. To address this challenge, we propose to design and evaluate the therapeutic efficacy of a novel simvastatin prodrug with better water solubility and bone affinity.

METHOD

The prodrug (SIM-PPi) was synthesized by directly conjugating a SIM trimer to a pyrophosphate (PPi). It was characterized and evaluated in vitro for its water solubility, osteotropicity, toxicity, anti-inflammatory and osteoinductive properties. It was then tested for anti-inflammatory and osteoinductive properties in vivo by three weekly injections into gingiva of a ligature-induced experimental periodontitis rat model.

RESULTS

In vitro studies showed that SIM-PPi has greatly improved water-solubility of SIM and shows strong binding to hydroxyapatite (HA). In macrophage culture, SIM-PPi inhibited LPS-induced pro-inflammatory cytokines (IL-1β, IL-6). In osteoblast culture, it was found to significantly increase alkaline phosphatase (ALP) activity with accelerated mineral deposition, confirming the osteogenic potential of SIM-PPi. When tested in vivo on an experimental periodontal bone-loss model, SIM-PPi exhibited a superior prophylactic effect compared to dose equivalent SIM in reducing inflammatory cells and in preserving alveolar bone structure, as shown in the histological and micro-CT data.

CONCLUSION

SIM-PPi may have the potential to be further developed for better clinical management of bone loss associated with periodontitis.

Pravastatin and Clopidogrel Combined Inhibit Intimal Hyperplasia in a Rat Carotid Endarterectomy Model

Intimal hyperplasia, resulting from a complex cascade of events involving platelets, leukocytes, and smooth muscle cells, may be inhibited by the HMG-CoA reductase inhibitor pravastatin, which demonstrates inhibition of platelet activity and leukocyte adhesion and may be associated with inhibition of vascular smooth muscle cell proliferation and migration. Clopidogrel, an adenosine diphosphate (ADP) receptor inhibitor, was shown to decrease platelet activity and aggregation but not intimal hyperplasia (IH). We postulated that the combination of both pravastatin and clopidogrel would significantly decrease IH in a rat carotid endarterectomy model. Male Sprague-Dawley rats (n = 18) divided by treatment regimen underwent treatment for 2 weeks both before and after an open carotid endarterectomy. Serum collected at the time of harvest was measured for C-reactive protein (CRP), platelet activity, and total serum cholesterol; carotid arteries were removed and processed for IH determination. Control rats (n = 7) received oral vehicle daily before and following endarterectomy. Pravastatin-alone rats (n = 6) received oral pravastatin (10 mg/kg/day) before and after endarterectomy. Pravastatin plus clopidogrel rats (n = 5) received oral pravastatin (10 mg/kg/day) plus a preendarterectomy bolus of oral clopidogrel (4.3 mg/kg) before endarterectomy and resumed pravastatin (10 mg/kg/day) plus oral clopidogrel (1 mg/kg/day) postendarterectomy. Pravastatin alone and pravastatin plus clopidogrel significantly decreased CRP compared to controls (120.2 ±11.2 and 134.1 ±9.9 vs 191.1 ±9.2 µg/mL, respectively p = 0.003 and p = 0.0024). CRP levels were not different between pravastatin alone and pravastatin plus clopidogrel (p = 0.35). Platelet activity was significantly decreased by pravastatin alone and pravastatin plus clopidogrel in comparison to controls (7.3 ±2.2 and 6.6 ±2.8 vs 19.2 ±6.1 platelet reactive units (PRU), respectively p = 0.048 and p = 0.045). No significant difference was noted in platelet activity between pravastatin alone and pravastatin plus clopidogrel (p = 0.89). Pravastatin plus clopidogrel significantly reduced serum cholesterol compared to control and pravastatin alone (84.0 ±6.6 vs 110.4 ±7.4 and 117.0 ±8.8 mg/dL, respectively p = 0.03 and p = 0.01). Pravastatin alone did not decrease serum cholesterol compared to controls (p = 0.54). IH was not reduced by pravastatin alone compared to controls (p = 0.61) but was significantly decreased by pravastatin plus clopidogrel in comparison to control and pravastatin alone (3.0 ±1.1 vs 46.3 ±13.7 and 37.4 ±14.6% luminal stenosis, respectively p = 0.01 and p = 0.05). Pravastatin plus clopidogrel significantly decreased CRP, platelet activity, total serum cholesterol, and IH while pravastatin alone decreased only CRP and platelet activity. Intimal hyperplasia reduction may therefore be dependent on other contributors, possibly growth factors, cytokines, and oxidative stress. The combination of pravastatin plus clopidogrel may have synergistic or even additional inhibitory effects on IH. Pravastatin plus clopidogrel was effective in decreasing IH in a rat carotid endarterectomy model and may prove a useful therapy for IH reduction in the clinical setting.

Multidimensional Contribution of Matrix Metalloproteinases to Atherosclerotic Plaque Vulnerability: Multiple Mechanisms of Inhibition to Promote Stability

The prevalence of atherosclerotic disease continues to increase, and despite significant reductions in major cardiovascular events with current medical interventions, an additional therapeutic window exists. Atherosclerotic plaque growth is a complex integration of cholesterol penetration, inflammatory cell infiltration, vascular smooth muscle cell (VSMC) migration, and neovascular invasion. A family of matrix-degrading proteases, the matrix metalloproteinases (MMPs), contributes to all phases of vascular remodeling. The contribution of specific MMPs to endothelial cell integrity and VSMC migration in atherosclerotic lesion initiation and progression has been confirmed by the increased expression of these proteases in plasma and plaque specimens. Endogenous blockade of MMPs by the tissue inhibitors of metalloproteinases (TIMPs) may attenuate proteolysis in some regions, but the progression of matrix degeneration suggests that MMPs predominate in atherosclerotic plaque, precipitating vulnerability. Plaque neovascularization also contributes to instability and, coupling the known role of MMPs in angiogenesis to that of atherosclerotic plaque growth, interest in targeting MMPs to facilitate plaque stabilization continues to accumulate. This article aims to review the contributions of MMPs and TIMPs to atherosclerotic plaque expansion, neovascularization, and rupture vulnerability with an interest in promoting targeted therapies to improve plaque stabilization and decrease the risk of major cardiovascular events.

The influence of statin therapy on platelet activity markers in hyperlipidemic patients after ischemic stroke

INTRODUCTION

Low-density lipoprotein cholesterol (LDL-C) has been reported to increase platelet activation. Reducing the level of LDL-C with statins induces important pleiotropic effects such as platelet inhibition. This association between platelet activity and statin therapy may be clinically important in reducing the risk of ischemic stroke. We investigated the effect of simvastatin therapy on platelet activation markers (platelet CD62P, sP-selectin, and platelet-derived microparticles (PDMPs)) in hyperlipidemic patients after ischemic stroke.

MATERIAL AND METHODS

The study group consisted of 21 hyperlipidemic patients after ischemic stroke confirmed by CT, and 20 healthy subjects served as controls. We assessed the CD62P expression on resting and thrombin-activated blood platelets. CD62P and PDMPs were analyzed by the use of monoclonal antibodies anti-CD61 and anti-CD62 on a flow cytometer. The level of sP-selectin in serum was measured by the ELISA (enzyme-linked immunosorbent assay) method. All markers were re-analyzed after 6 months of treatment with simvastatin (20 mg/day).

RESULTS

Hyperlipidemic patients presented a significantly higher percentage of CD62+ platelets and higher reactivity to thrombin compared to control subjects. After simvastatin therapy hyperlipidemic patients showed a reduction of the percentage of resting CD62P(+) platelets (p = 0.005) and a reduction of expression and percentage of CD62P(+) platelets after activation by thrombin (median p < 0.05; percentage: p = 0.001). A decrease of sP-selectin levels (p = 0.001) and percentage of PDMPs (p < 0.05) in this group was also observed.

CONCLUSIONS

HMG-CoA reductase inhibitor therapy in stroke patients with hyperlipidemia may be useful not only due to the lipid-lowering effect but also because of a significant role in reduction of platelet activation and reactivity.

Impact of statin treatment on strut coverage after drug-eluting stent implantation

PURPOSE

To evaluate the effect of statin treatment on strut coverage after drug-eluting stent (DES) implantation.

MATERIALS AND METHODS

In this study, 60 patients were randomly assigned to undergo sirolimus-eluting stent (SES) or biolimus-eluting stent (BES) implantation, after which patients were randomly treated with pitavastatin 2 mg or pravastatin 20 mg for 6 months. The degree of strut coverage was assessed by 6-month follow-up optical coherence tomography, which was performed in 52 DES-implanted patients.

RESULTS

The percentages of uncovered struts were 19.4±14.7% in pitavastatin-treated patients (n=25) and 19.1±15.2% in pravastatin-treated patients (n=27; p=0.927). A lower percentage of uncovered struts was significantly correlated with a lower follow-up low-density lipoprotein (LDL) cholesterol level (r=0.486; p=0.009) and a greater decline of the LDL cholesterol level (r=-0.456; p=0.015) in SES-implanted patients, but not in BES-implanted patients. In SES-implanted patients, the percentage of uncovered struts was significantly lower among those with LDL cholesterol levels of less than 70 mg/dL after 6 months of follow-up (p=0.025), but no significant difference in this variable according to the follow-up LDL cholesterol level was noted among BES-implanted patients (p=0.971).

CONCLUSION

Lower follow-up LDL cholesterol levels, especially those less than 70 mg/dL, might have a protective effect against delayed strut coverage after DES implantation. This vascular healing effect of lower LDL cholesterol levels could differ according to the DES type.

Statins and nitric oxide donors affect thrombospondin 1-induced chemotaxis

BACKGROUND

Thrombospondin 1 (TSP-1) induces vascular smooth muscle cell (VSMC) migration and intimal hyperplasia. Statins and nitric oxide (NO) donors decrease intimal hyperplasia. We previously showed that statins (long-term exposure) and NO donors inhibit TSP-1-induced VSMC chemotaxis.

HYPOTHESES

(1) Pretreatment with short-term statin will inhibit TSP-1-induced VSMC chemotaxis and (2) NO donors will enhance statin inhibition of TSP-1-induced or platelet-derived growth factor (PDGF)-induced VSMC chemotaxis.

METHODS

We examined these treatment effects on TSP-1-induced VSMC chemotaxis: (1) long-term (20 hours) versus short-term (20 minutes) pravastatin, (2) diethylenetriamine NONOate (DETA/NO) or S-nitroso-N-acetylpenicillamine (SNAP) in combination with pravastatin, and (3) comparison of TSP-1 to PDGF as a chemoattractant.

RESULTS

Pravastatin (long term or short term) inhibited TSP-1-induced chemotaxis. Diethylenetriamine NONOate and SNAP impeded statin inhibition of TSP-1-induced chemotaxis. Platelet-derived growth factor and TSP-1 had opposite effects on DETA/NO-pravastatin treatment.

CONCLUSION

Short-term statin pretreatment inhibited TSP-1-induced VSMC chemotaxis, suggesting a pleiotropic effect. High-dose NO reversed statin inhibition of TSP-1-induced chemotaxis, suggesting NO and statin combination therapies warrant further study.

Stimulatory interactions between human coronary smooth muscle cells and dendritic cells

Despite inflammatory and immune mechanisms participating to atherogenesis and dendritic cells (DCs) driving immune and non-immune tissue injury response, the interactions between DCs and vascular smooth muscle cells (VSMCs) possibly relevant to vascular pathology including atherogenesis are still unclear. To address this issue, immature DCs (iDCs) generated from CD14+ cells isolated from healthy donors were matured either with cytokines (mDCs), or co-cultured (ccDCs) with human coronary artery VSMCs (CASMCs) using transwell chambers. Co-culture induced DC immunophenotypical and functional maturation similar to cytokines, as demonstrated by flow cytometry and mixed lymphocyte reaction. In turn, factors from mDCs and ccDCs induced CASMC migration. MCP-1 and TNFα, secreted from DCs, and IL-6 and MCP-1, secreted from CASMCs, were primarily involved. mDCs adhesion to CASMCs was enhanced by CASMC pre-treatment with IFNγ and TNFα ICAM-1 and VCAM-1 were involved, since the expression of specific mRNAs for these molecules increased and adhesion was inhibited by neutralizing antibodies to the counter-receptors CD11c and CD18. Adhesion was also inhibited by CASMC pre-treatment with the HMG-CoA-reductase inhibitor atorvastatin and the PPARγ agonist rosiglitazone, which suggests a further mechanism for the anti-inflammatory action of these drugs. Adhesion of DCs to VSMCs was shown also in vivo in rat carotid 7 to 21 days after crush and incision injury. The findings indicate that DCs and VSMCs can interact with reciprocal stimulation, possibly leading to perpetuate inflammation and vascular wall remodelling, and that the interaction is enhanced by a cytokine-rich inflammatory environment and down-regulated by HMGCoA-reductase inhibitors and PPARγ agonists.

Dysfunction of vascular smooth muscle and vascular remodeling by simvastatin

Statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, are widely prescribed for hypercholesterolemia. With the increasing use of statins, numerous reports demonstrated that statins can cause damage to skeletal muscles. However, the toxicities of statins on vascular smooth muscle, which are essential to cardiovascular homeostasis, have not been previously described. Here, we examined the effects of simvastatin on the contractile function and the integrity of vascular smooth muscle in isolated rat thoracic aortic rings, primary cultured vascular smooth muscle cells (VSMCs) in vitro and rats in vivo. In aortic rings, simvastatin suppressed the normal agonist-induced contractile responses in time- and concentration-dependent manners (0.86 g ± 0.11 at 10 μM simvastatin for 24 h compared with 1.89 g ± 0.11 at control). The suppression persisted in the endothelium-denuded aortic rings and was irreversible even after wash-out of simvastatin. Simvastatin suppressed the contraction induced by Bay K8644, an activator of voltage-operated Ca²⁺ channel (VOCC) in rat aortic rings and abolished agonist-induced intracellular Ca²⁺ increase in VSMCs. The simvastatin-induced contractile dysfunction was reversed by the supplementation of mevalonate and geranylgeranylpyrophosphate, precursors for protein isoprenylation. Consistently, activation of RhoA, a representative isoprenylated protein, was disrupted by simvastatin in VSMCs and RhoA-mediated phosphorylation of MYPT1 and CPI-17, and tonic tension were also suppressed. Notably, prolonged treatment of simvastatin up to 48 h induced apoptosis of vascular smooth muscle in aortic rings. Most importantly, simvastatin treatment in vivo significantly attenuated the agonist-induced vasoconstriction in rats ex vivo and induced a decrease in luminal area of the vascular wall. Collectively, these results demonstrate that simvastatin can impair the normal vascular contractility by disturbing Ca²⁺ influx and RhoA activity, ultimately leading to apoptosis and structural remodeling.

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.

Effect of statin therapy in the outcome of bloodstream infections due to Staphylococcus aureus: a prospective cohort study

INTRODUCTION

Statins have pleiotropic effects that could influence the prevention and outcome of some infectious diseases. There is no information about their specific effect on Staphylococcus aureus bacteremia (SAB).

METHODS

A prospective cohort study including all SAB diagnosed in patients aged ≥18 years admitted to a 950-bed tertiary hospital from March 2008 to January 2011 was performed. The main outcome variable was 14-day mortality, and the secondary outcome variables were 30-day mortality, persistent bacteremia (PB) and presence of severe sepsis or septic shock at diagnosis of SAB. The effect of statin therapy at the onset of SAB was studied by multivariate logistic regression and Cox regression analysis, including a propensity score for statin therapy.

RESULTS

We included 160 episodes. Thirty-three patients (21.3%) were receiving statins at the onset of SAB. 14-day mortality was 21.3%. After adjustment for age, Charlson index, Pitt score, adequate management, and high risk source, statin therapy had a protective effect on 14-day mortality (adjusted OR = 0.08; 95% CI: 0.01-0.66; p = 0.02), and PB (OR = 0.89; 95% CI: 0.27-1.00; p = 0.05) although the effect was not significant on 30-day mortality (OR = 0.35; 95% CI: 0.10-1.23; p = 0.10) or presentation with severe sepsis or septic shock (adjusted OR = 0.89; CI 95%: 0.27-2.94; p = 0.8). An effect on 30-day mortality could neither be demonstrated on Cox analysis (adjusted HR = 0.5; 95% CI: 0.19-1.29; p = 0.15).

CONCLUSIONS

Statin treatment in patients with SAB was associated with lower early mortality and PB. Randomized studies are necessary to identify the role of statins in the treatment of patients with SAB.

Pleiotropic effects of simvastatin in physically trained ovariectomized rats

This study tested the hypothesis that simvastatin treatment can improve cardiovascular and autonomic functions and membrane lipoperoxidation, with an increased effect when applied to physically trained ovariectomized rats. Ovariectomized rats were divided into sedentary, sedentary+simvastatin and trained+simvastatin groups (n = 8 each). Exercise training was performed on a treadmill for 8 weeks and simvastatin (5 mg/kg) was administered in the last 2 weeks. Blood pressure (BP) was recorded in conscious animals. Baroreflex sensitivity was evaluated by the tachycardic and bradycardic responses to BP changes. Cardiac vagal and sympathetic effects were determined using methylatropine and propranolol. Oxidative stress was evaluated based on heart and liver lipoperoxidation using the chemiluminescence method. The simvastatin-treated groups presented reduced body weight and mean BP (trained+simvastatin = 99 ± 2 and sedentary+simvastatin = 107 ± 2 mmHg) compared to the sedentary group (122 ± 1 mmHg). Furthermore, the trained group showed lower BP and heart rate compared to the other groups. Tachycardic and bradycardic responses were enhanced in both simvastatin-treated groups. The vagal effect was increased in the trained+simvastatin group and the sympathetic effect was decreased in the sedentary+simvastatin group. Hepatic lipoperoxidation was reduced in sedentary+simvastatin (≈21%) and trained+simvastatin groups (≈57%) compared to the sedentary group. Correlation analysis involving all animals demonstrated that cardiac lipoperoxidation was negatively related to the vagal effect (r = -0.7) and positively correlated to the sympathetic effect (r = 0.7). In conclusion, improvement in cardiovascular and autonomic functions associated with a reduction of lipoperoxidation with simvastatin treatment was increased in trained ovariectomized rats.

Inhibitory effects and mechanisms of luteolin on proliferation and migration of vascular smooth muscle cells

Atherosclerosis (AS) is a complicated progress, involving many types of cells. Although the exact mechanisms of progression of atherosclerosis are uncertain, the balance of vascular smooth muscle cells (VSMCs) proliferation and apoptosis appears to play a pivotal role in the pathogenesis and progression of atherosclerosis, and much discussion has been undertaken to elucidate the detailed mechanisms, relevant gene expression and transduction pathways. Drug treatment has focused on ameliorating atherosclerosis. Some researchers have indicated that inhibiting VSMCs proliferation is involved in attenuating atherosclerosis. Luteolin is a kind of flavonoids naturally occurring in many plants and possesses beneficial effects on cardiovascular diseases. Luteolin can reduce VSMCs’ proliferation and migration and this reduction is stimulated by several factors. The aim of this review is to summarize the existing inhibitory effects and mechanisms of luteolin on proliferation and migration of VSMCs, and consider whether luteolin may be a potential candidate for preventing and treating atherosclerosis.

Clinical response to statins: mechanism(s) of variable activity and adverse effects

Statins represent a major advance in the treatment of hypercholesterolemia, a significant risk factor for atherosclerosis. There is, however, notable interindividual variation in the cholesterolemic response to statins, and the origin of this variability is poorly understood; pharmacogenetics has attempted to determine the role of genetic factors. Myopathy, further, has been reported in a considerable percentage of patients, but the mechanisms underlying muscle injury have yet to be fully characterized. Most statins are the substrates of several cytochrome P450s (CYP). CYP polymorphisms may be responsible for variations in hypolipidemic activity; inhibitors of CYPs, e.g. of CYP3A4, can significantly raise plasma concentrations of several statins, but consequences in terms of clinical efficacy are not uniform. Pravastatin and rosuvastatin are not susceptible to CYP inhibition but are substrates of the organic anion-transporting polypeptide (OATP) 1B1, encoded by the SLCO1B1 gene. Essentially all statins are, in fact, substrates of membrane transporters: SLCO1B1 polymorphisms can decrease the liver uptake, as well as the therapeutic potential of these agents, and may be linked to their muscular side-effects. A better understanding of the mechanisms of statin handling will help to minimize adverse effects and interactions, as well as to improve their lipid-lowering efficiency.

Do statins have a role in reduction/prevention of post-PCI restenosis?

The pathophysiology of post-PCI restenosis involves neointimal formation that consists of three phases: thrombosis (within 24 h), recruitment (3-8 days), and proliferation, which starts on day 8 of PCI. Various factors suggested to be predictors/risks for restenosis include C-reactive protein (CRP), inflammatory mediators (cytokines and adhesion molecules), oxygen radicals, advanced glycation end products (AGEs) and their receptors (RAGE), and soluble RAGE (sRAGE). The earlier noted factors produce thrombogenesis, vascular smooth muscle cell proliferation, and extracellular matrix formation. Statins have pleiotropic effects. Besides lowering serum cholesterol, they have various other biological effects including antiinflammatory, antithrombotic, CRP-lowering, antioxidant, antimitotic, and inhibition of smooth muscle cell proliferation. They inhibit matrix metalloproteinase and cyclooxygenase-2, lower AGEs, decrease expression of RAGE and increase levels of serum sRAGE. They also increase the synthesis of nitric oxide (NO) by increasing endothelial NO synthase expression and activity. Preprocedural statin therapy is known to reduce peri- and post-PCI myonecrosis and reduce the need for repeat revascularization. There is evidence that statin-eluting stents inhibit in-stent restenosis in animal models. It is concluded that because of the above attributes of statins, they are suitable candidates for reduction of post-PCI restenosis and post-PCI myonecrosis. The future directions for the use of statins in reduction of post-PCI restenosis and myonecrosis have been discussed.

Apposite insulin-like growth factor (IGF) receptor glycosylation is critical to the maintenance of vascular smooth muscle phenotype in the presence of factors promoting osteogenic differentiation and mineralization

Vascular calcification is strongly linked with increased morbidity and mortality from cardiovascular disease. Vascular calcification is an active cell-mediated process that involves the differentiation of vascular smooth muscle cells (VSMCs) to an osteoblast-like phenotype. Several inhibitors of this process have been identified, including insulin-like growth factor-I (IGF-I). In this study, we examined the role of the IGF receptor (IGFR) and the importance of IGFR glycosylation in the maintenance of the VSMC phenotype in the face of factors known to promote osteogenic conversion. IGF-I (25 ng/ml) significantly protected VSMCs from β-glycerophosphate-induced osteogenic differentiation (p < 0.005) and mineral deposition (p < 0.01). Mevalonic acid depletion (induced by 100 nm cerivastatin) significantly inhibited these IGF protective effects (p < 0.01). Mevalonic acid depletion impaired IGFR processing, decreased the expression of mature IGFRs at the cell surface, and inhibited the downstream activation of Akt and MAPK. Inhibitors of N-linked glycosylation (tunicamycin, deoxymannojirimycin, and deoxynojirimycin) also markedly attenuated the inhibitory effect of IGF-I on β-glycerophosphate-induced mineralization (p < 0.05) and activation of Akt and MAPK. These results demonstrate that alterations in the glycosylation of the IGFR disrupt the ability of IGF-I to protect against the osteogenic differentiation and mineralization of VSMCs by several interrelated mechanisms: decreased IGFR processing, reduced IGFR cell-surface expression, and reduced downstream signaling via the Akt and MAPK pathways. IGF-I thus occupies a critical position in the maintenance of normal VSMC phenotype and protection from factors known to stimulate vascular calcification.

Statin therapy is not associated with improved vascular access outcomes

BACKGROUND AND OBJECTIVES

Neointimal hyperplasia is the major cause of vascular access failure in hemodialysis patients. Statins reduce neointimal hyperplasia in experimental models, which may reduce access failure. The study presented here evaluated whether vascular access outcomes are superior in patients receiving statin therapy than in those not on statins.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A prospective computerized vascular access database was retrospectively queried to determine the access outcomes of 601 patients receiving an upper-arm fistula or graft at a single large dialysis center.

RESULTS

Primary fistula failure was observed in 37% of patients on statin therapy versus 38% not on statin therapy. Primary graft failure occurred in 20% of patients on statin therapy versus 14% not on statin therapy. A multiple variable logistic regression analysis including statin use, diabetes, coronary artery disease, peripheral artery disease, sex, and age found that only sex predicted primary fistula failure and graft failure. After excluding primary failures, cumulative fistula survival was similar for patients with or without statin therapy (hazard ratio [HR] 1.26; 95% confidence interval [CI] 0.76 to 2.16). Likewise, cumulative graft survival was similar for statin therapy versus no statin therapy (HR 0.88; 95% CI 0.59 to 1.32). Using a multivariable survival analysis model to predict cumulative fistula survival, only age predicted fistula failure (HR 1.21 per decade; 95% CI 1.02 to 1.44). None of the variables in this model predicted cumulative graft survival.

CONCLUSIONS

Statin therapy is not associated with improved fistula or graft outcomes in patients with chronic kidney disease.

Omega-3 fatty acids and atorvastatin affect connexin 43 expression in the aorta of hereditary hypertriglyceridemic rats

Statins and omega-3 polyunsaturated fatty acids (n-3 PUFA) reduce cardiovascular disease incidence during hypertriglyceridemia (HTG). To elucidate possible cardioprotective mechanisms, we focused on gap junction protein connexin 43 (Cx43). Its expression is disturbed during atherogenesis, but little information is available on its expression during HTG. Experiments were performed on adult male hereditary HTG (hHTG) rats treated with n-3 PUFA (30 mg/day) and atorvastatin (0.5 mg/100 g body weight per day) for 2 months. Cx43 expression and distribution in the aorta were investigated by using Western blotting and immunolabeling, followed by quantitative analysis. Transmission electronmicroscopy was used to study ultrastructure of endothelial contact sites. In contrast to age-matched Wistar, Cx43 expression in aorta of hHTG rats was significantly higher (p < 0.05), and prominent Cx43 immunospots were seen in tunica media and less in endothelium of hHTG rats. Changes in Cx43 expression were accompanied by local qualitative subcellular alterations of interendothelial connections. Treatment of hHTG rats with n-3 PUFA and atorvastatin markedly lowered Cx43 expression in aorta and modified connexin distribution in endothelium and media (p < 0.05 vs. untreated hHTG). The protective effect of treatment of HTG was observed on the structural integrity of the endothelium and was readily visible at the molecular level. Results indicate the involvement of altered Cx43 expression in vascular pathophysiology during HTG and during HTG treatment.

Interactions between cell death induced by statins and 7-ketocholesterol in rabbit aorta smooth muscle cells

BACKGROUND AND PURPOSE

7-Ketocholesterol, an oxysterol present in atherosclerotic lesions, induces smooth muscle cell (SMC) death, thereby destabilizing plaques. Statins protect patients from myocardial infarction, though they induce SMC apoptosis. We investigated whether statins and 7-ketocholesterol exerted additive cell death effects.

EXPERIMENTAL APPROACH

Cultured rabbit aorta SMCs (passage 2-6) were exposed to 7-ketocholesterol with or without fluvastatin, simvastatin or pravastatin. Uptake of neutral red (NR), monolayer protein, cleavage of the pan-caspase substrate Asp-Glu-Val-Asp-rhodamine110, cell morphology (light and electron microscopy) and processing of microtubule-associated protein 1 light chain 3 (LC3, immunoblot) were determined.

KEY RESULTS

NR uptake declined upon 18 h exposure to 25 microM 7-ketocholesterol (-41+/-3%, n=13), 100 microM fluvastatin (-59%) or 30-100 microM simvastatin (-28 to -74%). Oxysterol and high statin concentrations exerted additive effects, but lower concentrations (fluvastatin 10-30 microM, simvastatin 1-10 microM) partly reversed viability loss. 7-Ketocholesterol caused intense cytoplasmic vacuolization, processing of LC3-I to LC3-II, but little caspase activation (increase 29.5%). Fluvastatin (10-100 microM, 70-545% increase) and simvastatin (3-100 microM 43-322% increase) induced caspase activation without LC3 processing, but failed to activate caspases in 7-ketocholesterol-treated SMCs. Pravastatin up to 100 microM was always inactive.

CONCLUSIONS AND IMPLICATIONS

7-Ketocholesterol caused SMC death, mainly via autophagic vesicle formation with LC3 processing, whereas lipophilic statins evoked SMC apoptosis. Cell death following 7-ketocholesterol and low statin concentrations were not additive, presumably because the autophagic process interfered with statin-induced caspase activation. This further illustrates that drug effects in normal SMCs are not necessarily predictive for activities in atherosclerotic settings.

The effects of atorvastatin therapy on endothelial function in patients with coronary artery disease

Background

Statins improve the endothelial function in patients with coronary artery disease (CAD). However, they contribute to the substantial decrease in coronary heart disease by reducing plasma cholesterol levels. They also, reduce oxidative stress, stabilize the atherosclerotic plaque and inhibit inflammatory response. These functions of statins have been briefly described as pleiotropic effects. The aim of our study was to evaluate the effect of atorvastatin therapy on endothelial functions in patients with CAD.

Methods

Fourty-nine patients (40 men, 9 women, mean age 59 +/- 11 years) with diagnosed CAD were selected as the study group. The patients were given 10 mg/day atorvastatin for 12 weeks. If the target cholesterol levels has not been achieved 6 weeks after the treatment, then the daily atorvastatin dosage has been increased. The endothelial function was evaluated by flow mediated dilatation (FMD) of the brachial artery.

Results

It has been figured out that 12 weeks later, atorvastatin caused a statistically significant decrease in the plasma levels of LDL-cholesterol and total cholesterol (p < 0,0001). Meanwhile, it was determined that the FMD got statistically significant improved 12 weeks after the atorvastatin therapy (8,1%–4,2%, p < 0,001). However there was no statistically significant change in non-endothelium dependent dilatation (NID).

Conclusion

Endothelium derived vasodilatation (EBD), which was non-invasively detected via brachial artery ultrasonography, had statistically significant improvment within 12 weeks of atorvastatin therapy whereas non-endothelium dependent dilatation (NID) had no change.

Potential roles for statins in critically ill patients

The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are the most commonly prescribed agents for hypercholesterolemia and have revolutionized the management of hyperlipidemia and the area of cardiovascular risk reduction. However, recent data suggest that their effects go well beyond the lipid lowering seen with long-term use and may include acute antiinflammatory activity, anticoagulation, immunomodulation, as well as promotion of changes in smooth-muscle tone. Because of these data, promising research has begun into the use of these agents in various critical care areas such as the early phases of sepsis, bacteremia, and ischemic stroke. Recent data also show a decrease in cerebral vasospasm after subarachnoid hemorrhage, an area deficient in therapeutic options. More research is necessary to ascertain the true role of statins in the treatment of these various disorders. Nevertheless, the concept of a statin's role as being only a routine preventive therapy with benefits limited to patients undergoing extended treatment is rapidly becoming inaccurate.

Novel pharmacological approaches to the treatment of renal ischemia-reperfusion injury: a comprehensive review

Renal ischemia-reperfusion (I-R) contributes to the development of ischemic acute renal failure (ARF). Multi-factorial processes are involved in the development and progression of renal I-R injury with the generation of reactive oxygen species, nitric oxide and peroxynitrite, and the decline of antioxidant protection playing major roles, leading to dysfunction, injury, and death of the cells of the kidney. Renal inflammation, involving cytokine/adhesion molecule cascades with recruitment, activation, and diapedesis of circulating leukocytes is also implicated. Clinically, renal I-R occurs in a variety of medical and surgical settings and is responsible for the development of acute tubular necrosis (a characteristic feature of ischemic ARF), e.g., in renal transplantation where I-R of the kidney directly influences graft and patient survival. The cellular mechanisms involved in the development of renal I-R injury have been targeted by several pharmacological interventions. However, although showing promise in experimental models of renal I-R injury and ischemic ARF, they have not proved successful in the clinical setting (e.g., atrial natriuretic peptide, low-dose dopamine). This review highlights recent pharmacological developments, which have shown particular promise against experimental renal I-R injury and ischemic ARF, including novel antioxidants and antioxidant enzyme mimetics, nitric oxide and nitric oxide synthase inhibitors, erythropoietin, peroxisome-proliferator-activated receptor agonists, inhibitors of poly(ADP-ribose) polymerase, carbon monoxide-releasing molecules, statins, and adenosine. Novel approaches such as recent research involving combination therapies and the potential of non-pharmacological strategies are also considered.

EP2306 [2-(4-Biphenyl)-4-methyl-octahydro-1,4-benzoxazin-2-ol, hydrobromide], A Novel Squalene Synthase Inhibitor, Reduces Atherosclerosis in the Cholesterol-Fed Rabbit

EP2306 [2-(4-biphenyl)-4-methyl-octahydro-1,4-benzoxazin-2-ol, hydrobromide] inhibits squalene synthase and lipid biosynthesis and possesses antioxidant properties. We hypothesized that EP2306 can effectively modify circulating lipids and reduce atherosclerosis in the cholesterol-fed rabbit. Animals were fed a high-cholesterol diet for 4 weeks followed by 4 (phase 1 and 2) or 12 weeks (phase 3) of drug treatment while on high-cholesterol diet. In phase 1, the dose-effect relationship of EP2306 on lipids and atherosclerosis was established, and its most effective dose was determined (2 mg/kg). This dose reduced significantly total cholesterol (512 +/- 96 mg/dl before versus 320 +/- 124 mg/dl after treatment, p < 0.05) and atherosclerotic lesions compared with control animals. In phase 2, the effects of 2 mg/kg EP2306, 2.5 mg/kg simvastatin, and their combination were assessed. Although no significant effect on lipid parameters was observed, there was a significant reduction (35 +/- 5%, p < 0.05) of atherosclerotic lesions in animals treated with EP2306, a similar reduction with simvastatin, and a further reduction (48 +/- 7%, p < 0.05) when the two agents were combined. In animals treated for 12 weeks with the drugs (phase 3), only EP2306 significantly reduced atherosclerotic lesions by more than 50%, whereas simvastatin alone or in combination with EP2306 had no effect. Treatment with EP2306 did not adversely affect liver transaminases or cause any histopathological changes on various organs of the animals. In conclusion, we have shown that EP2306 inhibits atherosclerosis in vivo, indicating potential as a novel therapeutic agent for coronary artery disease and other atherosclerosis-related disorders.

Statins do not improve short-term survival in an oriental population with sepsis

OBJECTIVES

The aim of this study was to define the effect of statin on 30-day mortality in an oriental population with sepsis.

DESIGN

We conducted a retrospective study on patients with sepsis at National Taiwan University Hospital from 2001 to 2002. The effects of statins on 30-day mortality were evaluated based on clinical settings. Log-rank test and Cox regression analysis were performed using the proportional hazards assumption.

RESULTS

A total of 763 episodes of sepsis were reviewed; 454 consecutive patients were considered eligible. Among them, 104 (22.9%) took a statin at least 30 days before admission and during sepsis course, whereas the other 350 control (77.1%) did not. There was no significant difference of 30-day sepsis-related mortality between groups (19.2% vs 18.9%, P = .952). Statin treatment was not associated with decreased mortality at 30 days (P = .853; risk ratio, 0.95; 95% confidence interval, 0.53-1.68).

CONCLUSION

Short-term, sepsis-related mortality in a septic Taiwanese population was not reduced with statin treatment in our study. We concluded that statin therapy may have little effect on the survival of sepsis in oriental people, particularly in Taiwanese.

Geranylgeranylacetone inhibits ovarian cancer progression in vitro and in vivo

Geranylgeranylacetone (GGA), an isoprenoid compound, is an anti-ulcer drug developed in Japan. In our previous study, GGA was shown to inhibit ovarian cancer invasion by attenuating Rho activation [K. Hashimoto, K. Morishige, K. Sawada, M. Tahara, S. Shimizu, M. Sakata, K. Tasaka, Y. Murata, Geranylgeranylacetone inhibits lysophosphatidic acid-induced invasion of human ovarian carcinoma cells in vitro. Cancer 103 (2005) 1529-1536.]. In the present study, GGA treatment inhibited ovarian cancer progression in vitro and suppressed the tumor growth and ascites in the in vivo ovarian cancer model. In vitro analysis, treatment of cancer cells by GGA resulted in the inhibition of cancer cell proliferation, the inactivation of Ras, and the suppression of tyrosine phosphorylation of mitogen-activated protein kinase (MAPK). In conclusion, this is the first report that GGA inhibited ovarian cancer progression and the anti-tumor effect by GGA is, at least in part, derived not only from the suppression of Rho activation but also Ras-MAPK activation.

Statins and Peripheral Arterial Disease: Potential Mechanisms and Clinical Benefits

Peripheral arterial disease (PAD) is a manifestation of widespread atherosclerosis. Lipid modification (especially with statins) is a component of the treatment of patients with PAD since this condition is considered a coronary heart disease equivalent. This review considers the mechanism of action of statins in PAD. Statins have been shown to reduce the incidence of new coronary events in patients with PAD. However, surveys suggest that many such patients remain undertreated. Statins can also increase walking distance in patients with PAD. There is also evidence that statins can improve renal function in these patients. Several other actions of statins are considered in this review. PAD patients have an increased morbidity and mortality, largely due to myocardial infarction and stroke. Recognizing and treating these high-risk patients as early as possible should be a priority.

HMG-CoA reductase inhibitor fluvastatin prevents angiotensin II-induced cardiac hypertrophy via Rho kinase and inhibition of cyclin D1

HMG-CoA reductase inhibitors, so called statins, decrease cardiac events. Previous studies have shown that HMG-CoA reductase inhibitors inhibit cardiomyocyte hypertrophy in vitro and in vivo by blocking Rho isoprenylation. We have shown that the G1 cell cycle regulatory proteins cyclin D1 and Cdk4 play important roles in cardiomyocyte hypertrophy. However, the relation between Rho and cyclin D1 in cardiomyocyte is unknown. To investigate whether HMG-CoA reductase inhibitors prevent cardiac hypertrophy through attenuation of Rho and cyclin D1, we studied the effect of fluvastatin on angiotensin II-induced cardiomyocyte hypertrophy in vitro and in vivo. Angiotensin II increased the cell surface area and [(3)H]leucine uptake of cultured neonatal rat cardiomyocytes and these changes were suppressed by fluvastatin treatment. Angiotensin II also induced activation of Rho kinase and increased cyclin D1, both of which were also significantly suppressed by fluvastatin. Specific Rho kinase inhibitor, Y-27632 inhibited angiotensin II-induced cardiomyocyte hypertrophy and increased cyclin D1. Overexpression of cyclin D1 by adenoviral gene transfer induced cardiomyocyte hypertrophy, as evidenced by increased cell size and increased protein synthesis; this hypertrophy was not diminished by concomitant treatment with fluvastatin. Infusion of angiotensin II to Wistar rats for 2 weeks induced hypertrophic changes in cardiomyocytes, and this hypertrophy was prevented by oral fluvastatin treatment. These results show that an HMG-CoA reductase inhibitor, fluvastatin, prevents angiotensin II-induced cardiomyocyte hypertrophy in part through inhibition of cyclin D1, which is linked to Rho kinase. This novel mechanism discovered for fluvastatin could be revealed how HMG-CoA reductase inhibitors are preventing cardiac hypertrophy.

A new compound-specific pleiotropic effect of statins: modification of plasma gamma-tocopherol levels

Gamma tocopherol (gamma-T) is a recognized peroxynitrite scavenger, reputedly metabolized via the cytochrome P450 3A4 (CYP3A4). In this study, we assessed whether equipotent LDL-lowering doses of statins with or without inhibitory activity on CYP3A4 differently affect gamma-T metabolism. Patients with ATP III criteria for statin use (n=35) were randomly allocated to treatment with simvastatin 20mg/day or pravastatin 40 mg/day. Plasma lipids, alpha-tocopherol (alpha-T), gamma-T as well as the urinary excretion of the gamma-T metabolite 2,7,8-trimethyl-2-(2'carboxyethyl)-6-hydroxychroman (gamma-CEHC), were determined at baseline and after 6 weeks of treatment. Pravastatin and simvastatin equally reduced LDL-C (-42.8+/-2.9 and -42.1+/-3.0%) and alpha-T levels (-17.5+/-4.2 and -12.2+/-4.1%), and increased the alpha-T/LDL-C ratios (51.4+/-14.6 and 60.4+/-15%). Conversely, pravastatin did not affect whereas simvastatin significantly augmented plasma gamma-T levels (22+/-7.9%, p=0.009, between groups p=0.0045). Moreover, the gamma-T/LDL-C ratio increased significantly more with simvastatin than with pravastatin (124+/-23 versus 61.3+/-22.1%, p=0.05 between groups). In addition, pravastatin but not simvastatin increased the urinary excretion of gamma-CEHC (34.3+/-17.3%, p=0.056; between groups p=0.046). In conclusion, simvastatin and pravastatin produced distinct effects on gamma-T metabolism, presumably as a result of different statin-CYP interactions.

Short-term atorvastatin treatment does not modify neointimal morphology but reduces MMP-2 expression in normocholesterolemic rabbit stented arteries

The aim of our study was to explore some potential pleïotropic effects of atorvastatin, after stenting in the iliac arteries of normocholesterolemic rabbits. On day 0, 27 rabbits underwent stent implantation and were randomized into either the control group (standard chow, CTRL, n = 15) or the atorvastatin group (10 mg/kg/d per os, Ator, n = 12). On day 30, the stented arteries were harvested for histomorphometry and neointimal analysis [macrophages, matrix metalloproteinases (MMP-2), tissue inhibitor of metalloproteinase-2, vascular smooth muscle cells, and collagen]. Atorvastatin did not induce significant histomorphometric and inflammatory modifications but reduced neointimal expression of MMP-2 with no modification of tissue inhibitor of metalloproteinase-2, and also induced higher neointimal collagen content (Ator vs. CTRL: MMP-2: 0.05 +/- 0.03 vs. 0.70 +/- 0.20, P < 0.01; collagen: 17.0+/-0.7%/mm vs. 12.0 +/- 1.2%/mm(2) P < 0.01). Atorvastatin treatment also induced a significant decrease in neointimal vascular smooth muscle cells and cellular density (respectively: 2.0 +/- 0.2 vs. 1.4 +/- 0.2, P < 0.05; 5406 +/- 241 nuclei/mm(2) vs. 4402 +/- 163 nuclei/mm(2), P < 0.001). Our study provides new insights into the field of MMP response to stenting and the effects of statin therapy, which could have important implications in the field of in-stent restenosis.

Differential effects of statins on relevant functions of human monocyte-derived dendritic cells

Statins were shown to possess immunomodulating properties, but the mechanisms of statin effects on the immune system are poorly understood. We analyzed the influence of statins on professional antigen-presenting dendritic cells (DC). Immature DC were cultivated from monocytes of healthy donors. DC maturation was induced by lipopolysaccharide (LPS; 1 microg/mL). Unstimulated and LPS-stimulated DC were treated with simvastatin or atorvastatin (0.1-1 microM). The expression of CD40, CD83, CD86, and human leukocyte antigen-DR on unstimulated and LPS-stimulated DC was reduced significantly by statins, and the expression of Toll-like receptor 2 (TLR2) and TLR4 on LPS-stimulated DC was enhanced temporarily. Statins caused a significant reduction of endocytosis of fluorescein isothiocyanate-dextran by DC. Statins significantly inhibited the basal secretion of interleukin (IL)-6, IL-8, IL-12, and tumor necrosis factor alpha from unstimulated DC, and their release from LPS-stimulated DC was enhanced. In mixed leukocyte reaction, preincubation of LPS-stimulated DC with statins significantly suppressed their clustering with T cells and their ability to induce T cell proliferation, CD71, and CD25 up-regulation on T cells and the secretion of interferon-gamma and IL-2 from T cells. In conclusion, this study showed that statins suppressed endocytosis, basal secretion of proinflammatory cytokines, and the ability of DC to induce T cell proliferation, activation, and T helper cell type 1 differentiation. However, statin preincubation of LPS-stimulated DC caused a further increase in their secretion of proinflammatory cytokines.

The Effect of Six Different Statins on the Proliferation, Migration, and Invasion of Human Smooth Muscle Cells

Intimal hyperplasia (IH) can occur after any vascular injury and results from smooth muscle cells (SMC) proliferation, migration, and invasion into the subintimal space. The purpose of this study was to investigate the effect of six different statins on the proliferation, migration, and invasion of human venous SMC. The statins were all used at their Cmax concentrations. SMCs were used to construct growth curves in the presence of 10% fetal calf serum or 10% fetal calf serum supplemented with the six statins. Migration and invasion experiments were performed using modified Boyden chambers. The invasion experiments were performed using Matrigel coated plates. We found that all of the statins significantly inhibited SMC proliferation compared to the platelet-derived growth factor control (ranging from fluvastatin 33% of control to pravastatin 72% of control, P = 0.03). SMC migration through uncoated polycarbonate membranes in presence of the six statins was significantly reduced (ranging from lovastatin 43% to pravastatin 57% of control, P = 0.006). All six statins also significantly reduced SMC invasion (ranging from fluvastatin 65% to simvastatin 87% of control, P = 0.002). We conclude that the inhibitory effect of statins on SMC proliferation, migration, and invasion is a class, rather than drug specific effect.

Fluvastatin in the treatment of dyslipidemia associated with chronic kidney failure and renal transplantation

Premature atherosclerotic coronary heart disease driven by multiple risk factors is a major cause of morbidity and mortality among the 6 million patients in the United States with chronic renal failure. Consensus is that kidney failure and renal transplantation patients should be treated aggressively for dyslipidemia. Major medical literature databases were searched for published information about fluvastatin, a HMG-CoA reductase inhibitor, used in patients with impaired renal function. This article characterizes the dyslipidemia observed in these clinical settings and reviews the clinical experience with fluvastatin.