Similar Effects of Atorvastatin, Simvastatin and Pravastatin on Thrombogenic and Inflammatory Parameters in Patients with Hypercholesterolemia

Astragalus polysaccharides combined with simvastatin as an immunostimulant enhances the immune adjuvanticity of oil-in-water emulsion and immune responses in mice

Oil-in-water emulsion-based adjuvants have demonstrated acceptable safety in many disease indications, while their adjuvant activities for vaccines still need to be improved. Recently, the strategy of combining adjuvants with multiple types of immunostimulants has been shown to enhance immune responses. In this study, astragalus polysaccharides were combined with simvastatin as an immunostimulant to construct a compound O/W emulsion adjuvant. The formulations were optimized according to the OVA-specific antibody responses induced in mice. For this reason, high (5 mg/mL), medium (2.5 mg/mL), and low (1.25 mg/mL) concentrations of astragalus polysaccharides and high (10 mg/mL), medium (1 mg/mL), and low (0.1 mg/mL) concentrations of simvastatin were selected. The final optimal formulation of the immunostimulant was a high concentration of astragalus polysaccharides combined with a medium concentration of simvastatin. The optimal compound O/W emulsion adjuvant could induce effective humoral and cellular immune responses that were stronger and more stable than those induced by aluminum adjuvant and Freund's adjuvant. The OVA/HAPS-MSim-OE induced dramatically strong and persistent IgG expressions and Th1-polarized immune responses. What's more, the highest CD4⁺/CD8⁺lymphocyte ratios were observed in OVA/HAPS-MSim-OE group. In addition, compound O/W emulsion adjuvant groups significantly promoted the secretion of IFN-γ and IL-6, which also indicated that the compound O/W emulsion adjuvants could induce both enhanced Th1 and Th2-mediated immune responses but prefer the Th1-mediated ones. This study would contribute to an interesting and promising direction in the development of emulsion-based adjuvants.

Differential effect of statin use on coagulation markers: an active comparative analysis in the NEO study

Background

Statins are a potential treatment for venous thromboembolism (VTE) prophylaxis complementary to conventional anticoagulants without associated bleeding complications. This study aimed to compare pro-thrombotic activities of different classes of lipid-lowering drugs in an active comparator design and determine whether there is a relation between statin versus fibrate/niacin use and pro-coagulant factor outcomes.

Methods

This is a cross-sectional analysis of participants from the Netherlands Epidemiology of Obesity study using any class of lipid-lowering drugs, including any types of statins, niacin, and fibrates. We performed linear regression analyses to determine fibrinogen, factor (F) VIII, FIX, and FXI activity in statins versus fibrate/niacin users and adjusted for age, sex, tobacco smoking, body mass index (BMI), hypertension, diabetes, and prevalent cardiovascular disease.

Results

Among 1043 participants, the mean age was 58.4 ± 5.2 years, 61% were men, and the mean BMI was 31.3 ± 4.5 kg/m². Clinical characteristics were balanced between statin and fibrate/niacin users. Statin users had lower mean FXI (18.3 IU/dL, 95% confidence interval (CI) 9.4 to 27.3) levels compared to fibrate/niacin users. The level of FVIII (15.8 IU/dL, 95% CI − 0.003 to 31.6), and FIX (11.3 IU/dL, 95% CI − 0.4 to 23.2) were lower in statin users than fibrate/niacin users with marginal statistical significance.

Conclusion

Current statin use was associated with lower plasma levels of FXI than fibrate/niacin use. The effects on coagulation factors may, in part, explain the benefit of statin therapy rendered in primary and secondary prevention of VTE.

Mean Platelet Volume/Platelet Count Ratio and Risk of Progression in Glioblastoma

Objective

The mean platelet volume/platelet count (MPV/PC) ratio is an emerging biomarker in selected types of cancer. The objective of this study is to analyze the association of MPV/PC ratio with progression and survival in glioblastoma (GB) patients, with consideration of patient demographics, tumor morphology, extent of resection, molecular pathology, and oncological therapy.

Methods

One hundred ninety-one patients with newly diagnosed GB were analyzed retrospectively. MPV/PC ratio groups (≤ or >0.0575) were dichotomized into low-MPV/PC ratio (≤0.0575) and high-MPV/PC ratio (>0.0575) groups according to the most significant split in the log-rank test.

Results

A two-sided Fisher's exact test showed no significant differences in the confounders between the low- and high-MPV/PC ratio groups. The median progression-free survival (PFS) was 9.0 months (95% CI=8.0-10.0) in the low-MPV/PC ratio group (n=164) and 6.0 months (95% CI=3.0-8.9) in the high-MPV/PC group (n=28) (p=0.013). Multivariate Cox regression analysis including the O-6-methylguanine-DNA methyltransferase (MGMT) status, age (≤/>65 years), baseline Karnofsky Performance Status (KPS), and MPV/PC ratio showed high-MPV/PC ratio as a predictor of progression (p =0.04, HR=1.61, 95% CI=1.01-2.57). In the subgroup of IDH1 wild-type GBs, high MPV/PC ratio was still a significant predictor for shortened PFS (p=0.042, HR=1.60, 95% CI=1.02-2.52). MPV/PC ratio showed no significant effect in the overall survival (OS) analysis. Median OS was 15.0 months in the high-MPV/PC ratio group and 21.0 months in the low-MPV/PC ratio group (p=0.22).

Conclusion

MPV/PC ratio may independently predict the progression-free survival rates of patients with glioblastoma multiforme.

Baseline Serum C-Reactive Protein and Plasma Fibrinogen-Based Score in the Prediction of Survival in Glioblastoma

Objective: The present study investigates a score based on baseline C-reactive protein (CRP) and fibrinogen values (FC score) in 173 consecutive glioblastoma (GBM) patients.

Methods: The optimal cut-off value for fibrinogen and CRP was defined as 3.5 g/dl and 3.0 mg/L, respectively, according to previous reports. Patients with elevated CRP and fibrinogen were classified with a score of 2, those with an elevation of only one of these parameters were allocated a score of 1, and those without any abnormalities were assigned a score of 0.

Results: No significant differences in age, gender, tumor area, molecular pathology, physical status, or extent of resection were identified among the three groups defined by this score. Univariate survival analysis demonstrated that a high baseline FC score (≥1) is significantly associated with a shortened overall survival (OS) (HR: 1.52, 95% CI: 1.05–2.20, p = 0.027). A multivariate Cox regression analysis considering age (>65/≤65), extent of resection (GTR/STR), MGMT promoter status (hypermethylated/non-hypermethylated), and FC score (0/≥1) confirmed that an elevated FC score (≥1) is an independent predictor of shortened OS (HR: 1.71, 95% CI: 1.16–2.51, p = 0.006).

Conclusions: The baseline fibrinogen and CRP score thus serves as an independent predictor of OS in GBM. Further investigations of the role of inflammation in the prediction of a prognosis are needed.

A revised systematic review and meta-analysis on the effect of statins on D-dimer levels

BACKGROUND

D-dimers are generated during endogenous fibrinolysis of a blood clot and have a central role in diagnostic algorithms to rule out venous thromboembolism. HMG-CoA reductase inhibitors, more commonly called statins, are known to have effects independent of LDL-cholesterol lowering, including antithrombotic properties. An effect of statins on D-dimer levels has been reported in a prior systematic review and meta-analysis, but methodological shortcomings might have led to an overestimated effect. To re-evaluate the association between statins and D-dimer levels, we systematically reviewed all published articles on the influence of statins on D-dimer levels and conducted a novel meta-analysis (PROSPERO registration number CRD42017058932).

MATERIALS AND METHODS

We electronically searched EMBASE, Medline Epub, Cochrane, Web of Science and Google Scholar (100 top relevance) (date of last search: 5 October 2017). We included randomized controlled trials, cohort studies and cross-sectional studies. Two reviewers independently screened all articles retrieved and extracted data on study and patient characteristics, study quality and D-dimer levels.

RESULTS

Study-level meta-analysis involving 18,052 study participants showed lower D-dimer levels in those receiving statin treatment than controls (SMD: -0.165, 95% CI -0.234; -0.096, P = <0.001). Sensitivity analyses and additional analyses on treatment duration (<12 weeks vs ≥12 weeks) and type of statin (lipophilic or hydrophilic) did not modify this overall result.

CONCLUSION

This meta-analysis suggests an association between use of statins and reduction of D-dimer levels, independent of treatment duration and type of statin used. This effect is small but robust, and should be interpreted with caution.

Cardiovascular pleiotropic effects of statins and new onset diabetes: is there a common link: do we need to evaluate the role of KATP channels?

INTRODUCTION

Statins are considered the main stay of treatment in the prevention of cardio-vascular morbidity and mortality. They have multiple pleiotropic effects, like stabilization of atherosclerotic plaques, inhibition of platelet aggregation, and vascular smooth muscle proliferation; in addition to their lipid lowering action. Statins manifest these pleiotropic effects because they activate KATP channels in the cardiac and vascular tissue. Simultaneous activation of the KATP channels by statins in β cells of pancreas may inhibit insulin release which may lead to diabetes. Areas covered: Literature published between 1980 and 2016 on cholesterol biosynthesis, new onset diabetes and on the pleiotropic effects of statins, was reviewed. A comprehensive search on PubMed, Embase and Cochrane databases was carried out. Expert opinion: Statins exert their beneficial pleiotropic effects on the cardiovascular system by activating KATP channels in the cardiac and vascular tissue. However, simultaneous activation of KATP channels in the beta cells of pancreas leads to inhibition of insulin release. This disturbs the carbohydrate metabolism and probably leads to diabetes. In our opinion, use of stains should be more judicious and restricted to secondary prevention only.

Pediatric Statin Administration: Navigating a Frontier with Limited Data

Increasingly, children and adolescents with dyslipidemia qualify for pharmacologic intervention. As they are for adults, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are the mainstay of pediatric dyslipidemia treatment when lifestyle modifications have failed. Despite the overall success of these drugs, the magnitude of variability in dose-exposure-response profiles contributes to adverse events and treatment failure. In children, the cause of treatment failures remains unclear. This review describes the updated guidelines for screening and management of pediatric dyslipidemia and statin disposition pathway to assist the provider in recognizing scenarios where alterations in dosage may be warranted to meet patients' specific needs.

Anti-inflammatory Effects of Statins in Patients with Aortic Stenosis

Background: Aortic stenosis is an inflammatory process, as evidenced by increased tissue expression and serum levels of various endothelial cellular adhesion molecules. Aortic stenosis and atherosclerosis have many risk factors in common, including hypercholesterolemia. In atherosclerosis, statins lower cholesterol and display some anti-inflammatory activity. We hypothesized that statins might also have anti-inflammatory effects in patients with aortic stenosis.

Methods: This observational cross-sectional study measured levels of cellular adhesion molecules in 129 patients (88 male, mean age 68) with aortic stenosis (mean echo gradient 49 mm Hg, range 22 to 112) and compared levels in patients already on statin therapy for primary or secondary prevention of coronary artery disease, to those not on treatment. Concomitant conditions included hypertension (47%), diabetes (10%), and ischemic heart disease (54%). A comparison group consisted of 45 patients with stable ischemic heart disease.

Results: Patients on statins (35) were more likely to have hypertension (62% vs 42%, P = .05), but no significant differences existed in sex, age, concomitant ischemic heart disease, or diabetes. Statin-treated patients had a 20% lower vascular cellular adhesion molecule level than those without (484 ± 143 ng/L vs 604 ± 245 ng/L, P = .006). The reduction in cellular adhesion molecule levels was consistent in patients with aortic stenosis alone, aortic stenosis and ischemic heart disease, or ischemic heart disease alone. There were no differences in the levels of the other adhesion molecules between the three groups, or related to statin therapy.

Conclusion: Statin therapy is associated with reduced serum levels of vascular cellular adhesion molecules in patients with aortic stenosis. Vascular cellular adhesion molecule levels are similar in patients who have aortic stenosis, ischemic heart disease, or both. A prospective study is required to confirm this finding and to determine whether this suppression of endothelial inflammation translates into a slowing of the progression of aortic stenosis.

Treatment with atorvastatin attenuates progression of insulin resistance and pancreatic fibrosis in the Otsuka Long-Evans Tokushima fatty rats

PURPOSE

The effects of statins on insulin resistance (IR) and type 2 diabetes mellitus (T2DM) are still controversial and its effects on pancreatic fibrosis are poorly defined. The purpose of this study is to examine the effects of atorvastatin on these issues using the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, an animal model of IR, T2DM and pancreatic fibrosis.

METHODS

Male OLETF rats were divided into 2 groups at 6weeks of age. The first group received a standard diet until the end of experimental period at age 28weeks. The second group was given a diet containing 0.05% atorvastatin from 6weeks of age, before the onset of IR and pancreatic fibrosis. The age-matched Long-Evans Tokushima Otsuka rats without presence of IR, T2DM and pancreatic fibrosis, received a standard diet and were used as a normal control.

RESULTS

Atorvastatin slightly decreased serum fasting glucose and insulin levels, but significantly improved index of IR compared with the untreated OLETF rats. In addition, atorvastatin markedly decreased transforming growth factor-β1 mRNA expression, myeloperoxidase activity and proportion of fibrotic area, and elevated superoxide dismutase activity in the pancreas compared with the untreated OLETF rats.

CONCLUSIONS

These findings suggest that atorvastatin exerts favorable influence on progression of IR and pancreatic inflammation and fibrosis via pleiotropic effect such as anti-oxidative property.

Circulating Thrombotic Risk Factors in Young Patients with Coronary Artery Disease Who Are on Statins and Anti-platelet Drugs

Thrombotic risk factors may contribute to premature coronary artery disease (CAD), in addition to the conventional risk factors. There is paucity of data on studies evaluating the role of thrombotic factors in premature CAD in Indian patients. Thus a case-control study was performed to evaluate the role of thrombotic and atherogenic factors in young patients with angiographically proven CAD who are on treatment with statins and anti-platelet drugs. 152 patients (≤55 years) with angiographically proven CAD and 102 asymptomatic controls were recruited. Clinical and biochemical data were obtained in both groups. Blood levels of thrombotic factors-fibrinogen, antithrombin-III, tissue-plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), von-Willebrand factor (v-WF), lipoprotein(a) [Lp(a)] and homocysteine were analyzed. Patients had high levels of conventional CAD risk factors (diabetes mellitus, smoking, hypertension, dyslipidemia and positive family history) compared to controls. Logistic regression analysis revealed that low antithrombin-III (odds ratio/OR 11.2; 95 % confidence interval/CI 2.29-54.01), high fibrinogen (OR 6.04; 95 % CI 1.09-33.21) and high Lp(a) (OR 4.54; 95 % CI 0.92-22.56), as important, independent risk factors in patients. PAI-1(OR 0.15; 95 % CI 0.03-0.69) levels were significantly lower in patients. But other thrombotic risk factors studied (t-PA, v-WF and homocysteine) were comparable among patients and controls. The treatment using statins and anti-platelet drugs might be contributing to the control of some of the thrombotic risk factors. The strategies aiming at lowering the levels of thrombotic risk factors along with conventional risk factors may be useful in primary and secondary prevention of CAD.

Lipid-lowering efficacy of atorvastatin

BACKGROUND

This represents the first update of this review, which was published in 2012. Atorvastatin is one of the most widely prescribed drugs and the most widely prescribed statin in the world. It is therefore important to know the dose-related magnitude of effect of atorvastatin on blood lipids.

OBJECTIVES

Primary objective To quantify the effects of various doses of atorvastatin on serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol and triglycerides in individuals with and without evidence of cardiovascular disease. The primary focus of this review was determination of the mean per cent change from baseline of LDL-cholesterol. Secondary objectives • To quantify the variability of effects of various doses of atorvastatin.• To quantify withdrawals due to adverse effects (WDAEs) in placebo-controlled randomised controlled trials (RCTs).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 11, 2013), MEDLINE (1966 to December Week 2 2013), EMBASE (1980 to December Week 2 2013), Web of Science (1899 to December Week 2 2013) and BIOSIS Previews (1969 to December Week 2 2013). We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of atorvastatin on blood lipids over a duration of three to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included and extracted data. We collected information on withdrawals due to adverse effects from placebo-controlled trials.

MAIN RESULTS

In this update, we found an additional 42 trials and added them to the original 254 studies. The update consists of 296 trials that evaluated dose-related efficacy of atorvastatin in 38,817 participants. Included are 242 before-and-after trials and 54 placebo-controlled RCTs. Log dose-response data from both trial designs revealed linear dose-related effects on blood total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides. The Summary of findings table 1 documents the effect of atorvastatin on LDL-cholesterol over the dose range of 10 to 80 mg/d, which is the range for which this systematic review acquired the greatest quantity of data. Over this range, blood LDL-cholesterol is decreased by 37.1% to 51.7% (Summary of findings table 1). The slope of dose-related effects on cholesterol and LDL-cholesterol was similar for atorvastatin and rosuvastatin, but rosuvastatin is about three-fold more potent. Subgroup analyses suggested that the atorvastatin effect was greater in females than in males and was greater in non-familial than in familial hypercholesterolaemia. Risk of bias for the outcome of withdrawals due to adverse effects (WDAEs) was high, but the mostly unclear risk of bias was judged unlikely to affect lipid measurements. Withdrawals due to adverse effects were not statistically significantly different between atorvastatin and placebo groups in these short-term trials (risk ratio 0.98, 95% confidence interval 0.68 to 1.40).

AUTHORS' CONCLUSIONS

This update resulted in no change to the main conclusions of the review but significantly increases the strength of the evidence. Studies show that atorvastatin decreases blood total cholesterol and LDL-cholesterol in a linear dose-related manner over the commonly prescribed dose range. New findings include that atorvastatin is more than three-fold less potent than rosuvastatin, and that the cholesterol-lowering effects of atorvastatin are greater in females than in males and greater in non-familial than in familial hypercholesterolaemia. This review update does not provide a good estimate of the incidence of harms associated with atorvastatin because included trials were of short duration and adverse effects were not reported in 37% of placebo-controlled trials.

Anticoagulant effects of statins and their clinical implications

There is evidence indicating that statins (3-hydroxy-methylglutaryl coenzyme A reductase inhibitors) may produce several cholesterol-independent antithrombotic effects. In this review, we provide an update on the current understanding of the interactions between statins and blood coagulation and their potential relevance to the prevention of venous thromboembolism (VTE). Anticoagulant properties of statins reported in experimental and clinical studies involve decreased tissue factor expression resulting in reduced thrombin generation and attenuation of pro-coagulant reactions catalysed by thrombin, such as fibrinogen cleavage, factor V and factor XIII activation, as well as enhanced endothelial thrombomodulin expression, resulting in increased protein C activation and factor Va inactivation. Observational studies and one randomized trial have shown reduced VTE risk in subjects receiving statins, although their findings still generate much controversy and suggest that the most potent statin rosuvastatin exerts the largest effect.

Potential role for statins in sickle cell disease

The complex pathophysiology of sickle cell disease (SCD) is remarkably similar to that observed in other chronic vascular diseases and involves multiple biologic pathways triggered by ischemia reperfusion injury, coagulation activation, and inflammation. Statins are potent lipid-lowering agents commonly used to reduce the risk of cardiovascular disease. Independent of their lipid lowering effect, statins have been shown to down-regulate inflammatory mediators and endothelial adhesion molecules, reduce tissue factor expression and restore nitric oxide bioavailability. The pleiotropic effects of statins make these agents attractive therapeutic candidates for SCD. This article reviews available evidence for the potential role of statins in SCD.

Lipid lowering efficacy of atorvastatin

BACKGROUND

Atorvastatin is one of the most widely prescribed drugs and the most widely prescribed statin in the world. It is therefore important to know the dose-related magnitude of effect of atorvastatin on blood lipids.

OBJECTIVES

To quantify the dose-related effects of atorvastatin on blood lipids and withdrawals due to adverse effects (WDAE).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library Issue 4, 2011, MEDLINE (1966 to November 2011), EMBASE (1980 to November 2011), ISI Web of Science (1899 to November 2011) and BIOSIS Previews (1969 to November 2011). No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of atorvastatin on blood lipids over a duration of 3 to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. WDAE information was collected from the placebo-controlled trials.

MAIN RESULTS

Two hundred fifty-four trials evaluated the dose-related efficacy of atorvastatin in 33,505 participants. Log dose-response data revealed linear dose-related effects on blood total cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides. Combining all the trials using the generic inverse variance fixed-effect model for doses of 10 to 80 mg/day resulted in decreases of 36% to 53% for LDL-cholesterol. There was no significant dose-related effects of atorvastatin on blood high-density lipoprotein (HDL)-cholesterol. WDAE were not statistically different between atorvastatin and placebo for these short-term trials (risk ratio 0.99; 95% confidence interval 0.68 to 1.45).

AUTHORS' CONCLUSIONS

Blood total cholesterol, LDL-cholesterol and triglyceride lowering effect of atorvastatin was dependent on dose. Log dose-response data was linear over the commonly prescribed dose range. Manufacturer-recommended atorvastatin doses of 10 to 80 mg/day resulted in 36% to 53% decreases of LDL-cholesterol. The review did not provide a good estimate of the incidence of harms associated with atorvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 37% of the placebo-controlled trials.

Highly upregulated expression of CD36 and MSR1 in circulating monocytes of patients with acute coronary syndromes

Acute Coronary Syndromes (ACS) are a group of disorders caused by the significant reduction of circulation in coronary arteries. The most common reason of the dysfunction is a blood clot formed in place of plaque rupture. The role of scavenger receptors in development and progression of atherosclerosis has been confirmed in many animal experiments, however the knowledge about contribution of the receptors in the development of ACS symptoms in humans still remains insufficient. The aim of this work was to define the expression of two scavenger receptors: CD36 and MSR1 in monocytes of patients with ACS after the onset of symptoms and after the 6 months of treatment. The analysis of CD36 and MSR1 expression was carried out with the use of real-time PCR and flow cytometry. Analyses of lipid and glucose concentration in blood and the level of inflammatory markers in plasma were performed additionally for all ACS patients. All data obtained during the research were analyzed using statistical tests, such as Mann Whitney test, Wilcoxon test, or correlation. In all patients with symptoms of ACS the amount of CD36 and MSR1 mRNA in circulating monocytes, as well as the density of both receptors on the cells surface was significantly higher. Re-analysis of subjects after 6 months of treatment, showed a significant decrease in the CD36 and MSR1 expression in all patients who received atorvastatin. The results of presented studies demonstrate that both investigated receptors are involved in the development and/or progression of ACS.

Administration of simvastatin after kainic acid-induced status epilepticus restrains chronic temporal lobe epilepsy

In this study, we examined the effect of chronic administration of simvastatin immediately after status epilepticus (SE) on rat brain with temporal lobe epilepsy (TLE). First, we evaluated cytokines expression at 3 days post KA-lesion in hippocampus and found that simvastatin-treatment suppressed lesion-induced expression of interleukin (IL)-1β and tumor necrosis factor-α (TNF-α). Further, we quantified reactive astrocytosis using glial fibrillary acidic protein (GFAP) staining and neuron loss using Nissl staining in hippocampus at 4-6 months after KA-lesion. We found that simvastatin suppressed reactive astrocytosis demonstrated by a significant decrease in GFAP-positive cells, and attenuated loss of pyramidal neurons in CA3 and interneurons in dentate hilar (DH). We next assessed aberrant mossy fiber sprouting (MFS) that is known to contribute to recurrence of spontaneous seizure in epileptic brain. In contrast to the robust MFS observed in saline-treated animals, the extent of MFS was restrained by simvastatin in epileptic rats. Attenuated MFS was related to decreased neuronal loss in CA3 and DH, which is possibly a mechanism underlying decreased hippocampal susceptibility in animal treated with simvastatin. Electronic encephalography (EEG) was recorded during 4 to 6 months after KA-lesion. The frequency of abnormal spikes in rats with simvastatin-treatment decreased significantly compared to the saline group. In summary, simvastatin treatment suppressed cytokines expression and reactive astrocytosis and decreased the frequency of discharges of epileptic brain, which might be due to the inhibition of MFS in DH. Our study suggests that simvastatin administration might be a possible intervention and promising strategy for preventing SE exacerbating to chronic epilepsy.

Effects of short-term treatment with atorvastatin in smokers with asthma--a randomized controlled trial

Background

The immune modulating properties of statins may benefit smokers with asthma. We tested the hypothesis that short-term treatment with atorvastatin improves lung function or indices of asthma control in smokers with asthma.

Methods

Seventy one smokers with mild to moderate asthma were recruited to a randomized double-blind parallel group trial comparing treatment with atorvastatin (40 mg per day) versus placebo for 4 weeks. After 4 weeks treatment inhaled beclometasone (400 μg per day) was added to both treatment arms for a further 4 weeks. The primary outcome was morning peak expiratory flow after 4 weeks treatment. Secondary outcome measures included indices of asthma control and airway inflammation.

Results

At 4 weeks, there was no improvement in the atorvastatin group compared to the placebo group in morning peak expiratory flow [-10.67 L/min, 95% CI -38.70 to 17.37, p = 0.449], but there was an improvement with atorvastatin in asthma quality of life score [0.52, 95% CI 0.17 to 0.87 p = 0.005]. There was no significant improvement with atorvastatin and inhaled beclometasone compared to inhaled beclometasone alone in outcome measures at 8 weeks.

Conclusions

Short-term treatment with atorvastatin does not alter lung function but may improve asthma quality of life in smokers with mild to moderate asthma.

Trial Registration

Clinicaltrials.gov identifier: NCT00463827

Simvastatin reduces sympathetic activity in men with hypertension and hypercholesterolemia

Beyond their hypolipidemic effect, statins reduce cardiovascular risk in hypertensive subjects via various mechanisms; one suggested mechanism is that they reduce sympathetic activity. We investigated the hypothesis that simvastatin decreased muscle sympathetic nerve activity (MSNA) in 31 hypertensive subjects with hypercholesterolemia (aged 38.7 ± 10 years). In this randomized, placebo-controlled, double-blinded study, patients were treated with simvastatin (40 mg day(-1); n=15) or placebo (n=16) for 8 weeks. Before and after treatment, we measured MSNA, blood pressure and heart rate. Baroreceptor control of the heart rate, or baroreceptor sensitivity (BRS), was computed by the sequence method, a cross-analysis of systolic blood pressure and the electrocardiogram R-R interval. Blood samples were tested for plasma levels of catecholamines, neuropeptide Y, aldosterone, endothelin and renin activity. Simvastatin significantly reduced MSNA (from 36.5 ± 5 to 27.8 ± 6 bursts per min, P=0.001), heart rate (from 77 ± 6.7 to 71 ± 6.1 beats per min, P=0.01) and both total and low-density lipoprotein cholesterol (from 249 ± 30.6 to 184 ± 28.3 mg dl(-1), P=0.001 and from 169 ± 30.6 to 117 ± 31.2 mg dl(-1), P=0.01, respectively). Simvastatin also improved BRS (from 10.3 ± 4.1 to 17.1 ± 4.3 ms per mm Hg, P=0.04). No changes were observed in systolic or diastolic blood pressures, or in plasma levels of catecholamines, neuropeptide Y, endothelin, aldosterone and renin activity. After simvastatin therapy, MSNA and BRS were inversely related (r=-0.94, P<0.05). In conclusion, we found that, in patients with hypertension and hypercholesterolemia, simvastatin reduced MSNA, and this was related to increased baroreceptor sensitivity.

Is there a role for statins in atrial fibrillation?

3-Hydroxy-3-methyl-glutaryl-CoA reductase inhibitors (statins) are some of the most commonly prescribed drugs in the world. While lipid modification remains the primary function of statins, there has been increasing interest in its potential pleiotropic effects, particularly as an anti-inflammatory agent in its role as an antiarrhythmic. Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and carries with it a significant burden in both morbidity and mortality. Treatment for AF currently involves either rate or rhythm control where both have demonstrable associated risks. Rate control necessitates anticoagulation, which can cause life-threatening bleeding, while rhythm control has a poor side-effect profile that may lead to greater mortality and may not completely eliminate the need for anticoagulation. Considering this pressing need for novel therapeutic interventions in AF, this long overdue systematic review explores the potential role of statins in the treatment and prevention of AF. Physicians, especially cardiologists, need to be aware of the host of currently available literature and, more importantly, need to be stimulated to generate discussion and formulate studies that will help debate the issues under the most erudite standards.

Long-term benefits after treatment of traumatic brain injury with simvastatin in rats

OBJECTIVE

This study was designed to investigate the long-term effects of simvastatin treatment after traumatic brain injury (TBI) in rats.

METHODS

Adult female Wistar rats (n = 24) were injured with controlled cortical impact and divided into 3 groups. The first 2 groups were treated with simvastatin (0.5 or 1.0 mg/kg) administered orally for 14 days starting 1 day after TBI. The third group (control) received phosphate-buffered saline orally for 14 days. Neurological functional outcome was measured with modified neurological severity scores performed 1 day before TBI; on days 1, 4, 7, 14 after TBI; and biweekly thereafter. All animals were sacrificed 3 months after TBI. Brain tissues of half of the animals were processed for preparation of paraffin-embedded sections for immunohistological studies. The remaining half were frozen for enzyme-linked immunosorbent assay studies for quantification of brain-derived neurotrophic factor (BDNF) in the hippocampus and cortex.

RESULTS

The results showed that both doses of simvastatin significantly improved functional outcome compared with the control, with no difference between the 2 doses. Simvastatin treatment of 1.0 mg/kg increased the number of morphologically intact neurons in the hippocampus, but treatment of 0.5 mg/kg had no significant effect. Enzyme-linked immunosorbent assay studies showed that 0.5 mg/kg simvastatin significantly increased BDNF levels within the hippocampus, but 1.0 mg/kg had no significant effect. Neither dose had any effect on BDNF levels within the cortex.

CONCLUSION

Simvastatin treatment provides long-lasting functional improvement after TBI in rats. It also enhances neuronal survival in the hippocampus and increases BDNF levels in the hippocampus secondary to simvastatin treatment.

Endogenous tissue plasminogen activator and risk of recurrent cardiac events after an acute coronary syndrome in the MIRACL study

OBJECTIVE

To examine the relationship of baseline tissue plasminogen activator (t-PA) to early cardiovascular risk after an acute coronary syndrome, and the effect of intensive statin therapy.

METHODS

We measured plasma t-PA in 2860 of the 3086 (93%) subjects in the MIRACL study, an international randomized trial of atorvastatin 80mg daily versus placebo in patients with acute coronary syndromes. The relationship of t-PA to death, non-fatal acute myocardial infarction, cardiac arrest, or worsening angina over 16 weeks was assessed by Cox Proportional Hazards. D-dimer was measured in a random sample of 395 subjects.

RESULTS

Higher baseline t-PA was significantly related to the risk of recurrent events (HR=1.25, p=0.0014). This relationship was unaffected by adjustment for age, sex, troponin, hsCRP, and lipids (HR=1.17, p=0.029), but was attenuated by adjustment including body mass index and smoking (HR=1.14, p=0.08). D-dimer and t-PA concentrations were not related. Atorvastatin reduced the risk of recurrent events, but did not affect t-PA or D-dimer concentrations or the relationship of t-PA to outcomes.

CONCLUSION

In patients with acute coronary syndromes, increasing t-PA concentration was related to a higher early risk of recurrent events, paradoxically reflecting impaired endogenous fibrinolysis. This relationship is due in part to the association of t-PA with age, body mass index and smoking. Although statins lower the risk of recurrent events after acute coronary syndromes, it is unlikely that this benefit is achieved through thrombolytic and fibrinolytic pathways.

Tissue factor +5466A>G polymorphism determines thrombin formation following vascular injury and thrombin-lowering effects of simvastatin in patients with ischemic heart disease

OBJECTIVE

We examined the hypothesis that the +5466A>G variant (rs3917643) of the tissue factor (TF) gene is associated with thrombin formation following simvastatin in patients with ischemic heart disease (IHD).

METHODS AND RESULTS

Prothrombin 1.2 fragments (F1.2) and thrombin-antithrombin complexes (TAT) were assessed in 95 men with stable IHD, aged 54.4+/-6.8 years, in blood collected every 60s from the bleeding-time wounds before and after a 3-month simvastatin administration (40 mg/day). We identified 16 patients with the TF +5466AG genotype and 79 subjects with the +5466AA genotype. Baseline maximum rates of F1.2 and TAT formation and their maximum levels at the site of vascular injury, but not in venous blood, were higher in +5466G allele carriers than in those with +5466AA genotype (P<0.0001). The magnitude of reduction in maximum rates of F1.2 and TAT formation following simvastatin was larger (P<0.001) in +5466G allele carriers than in +5466AA subjects. The degree of decrease in maximum local levels of F1.2 and TAT after simvastatin was similar in both genotype groups. The presence of the +5466G allele was independently associated with the maximum velocity of F1.2 and TAT generation and maximum levels of both markers before and after simvastatin in multiple regression models (P<0.01 for all analyses). Local thrombin generation, in +5466AG and +5466AA subjects, showed no significant correlations with lipid variables.

CONCLUSIONS

Thrombin formation following vascular injury and thrombin-lowering effect of statins in patients with IHD are at least in part genetically determined by the TF +5466A>G polymorphism.

Differences in cardiovascular event rates between atorvastatin and simvastatin among new users: managed-care experience

OBJECTIVE

Recent clinical trials and observational studies have suggested that reduction in low-density lipoprotein cholesterol (LDL-C) does not account for all differences among statins' effects on cardiovascular (CV) events, but that these effects may vary with time. Using a large US managed-care claims data set for 2002-2005, we assessed whether a difference in the rate of inpatient CV event rates could be observed between new atorvastatin and simvastatin users taking doses with comparable LDL-C-lowering potency, when prior risk factors are controlled and varying observation periods are employed.

RESEARCH DESIGN AND METHODS

Eligible patients had a 6-month period of no statin use prior to the initial statin prescription, an initial statin dosage of either 20 or 40 mg of simvastatin or 10 or 20 mg of atorvastatin (the most commonly used doses of both drugs), a 0 to 3-month 'qualifying period' after the first prescription to allow for varying minimum lengths of statin use, and no statin switches. In the primary analysis, patients were observed until an event or significant non-adherence occurred, up to 3.5 years; in secondary analyses, maximum 3-month, 6-month and 1-year observation periods were used. The primary endpoint was the first inpatient admission due to a CV event after the end of the qualifying period; multivariate Cox regression analysis controlled for a variety of demographic and CV risk characteristics and statin type.

RESULTS

At baseline, simvastatin users had significantly higher observed risk factors and higher subsequent, unadjusted CV event rates. In the primary Cox regression analyses, the CV event hazard rates for atorvastatin ranged from 0.899 (1-month qualifying period, p = 0.027) to 0.936 (3-month qualifying period, p = 0.33) versus simvastatin. Cox-based hazard rates for atorvastatin during 3-month to 1-year observation periods ranged from 0.908 to 0.915 for the 0-day qualifying period and from 0.851 to 0.884 for the 1-month qualifying period cohort (all p < 0.05); rates for the 3-month qualifying period cohort remained non-significant.

LIMITATIONS

Since this was not a prospective randomized study, there is the potential for unobserved risk factors to be responsible for some or all of the differences observed.

CONCLUSIONS

These results indicate an association between atorvastatin use and lower CV event rates, particularly in the first year of use, when observable risk factor differences are controlled. The implied absolute risk reduction of 2-3 events per 1000 patients per year may be considered clinically significant when viewed relative to major clinical trial results.

Effect of atorvastatin on endothelial function and inflammation in long-duration type 1 diabetic patients without coronary heart disease and arterial hypertension

AIM

We evaluated the ability of atorvastatin, an HMG-CoA reductase inhibitor, to affect endothelial function and inflammation in long-duration (>10 years) type 1 diabetes mellitus (T1DM) patients without coronary heart disease (CHD) and arterial hypertension (AH).

METHODS AND RESULTS

We randomized 204 Caucasians with long-duration T1DM into either the atorvastatin 40 mg/day plus hypolipaemic diet group (n = 154) or the placebo plus hypolipaemic diet group (n = 50) for 6 months. Endothelium-dependent flow-mediated (FMD) and endothelium-independent flow-mediated vasodilatation, serum levels of plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor (vWF) and high sensitivity C-reactive protein (hs-CRP) were estimated before and after treatment. After 6 months of therapy, FMD was increased by 44% in the atorvastatin plus diet group compared with the placebo plus diet group. Treatment with atorvastatin led to a significant reduction in levels of PAI-1 and hs-CRP; however, the elevation of vWF level was observed. In the placebo plus diet group, we observed a significant reduction in levels of hs-CRP but not of vWF and PAI-1.

CONCLUSIONS

Atorvastatin improves endothelial function and reduces some proinflammatory and prothrombotic markers of atherosclerosis in T1DM patients without CHD and AH. The surprising effect of atorvastatin on serum vWF levels in T1DM requires further study.

Effect of statins on soluble CD40 ligand in hypercholesterolemic Type 2 diabetic patients

Hypercholesterolemia and Type 2 diabetes are well-recognized risk factors for cardiovascular disease, promoted by a condition of subclinical inflammation and a hypercoagulable state. Soluble CD40 ligand (sCD40L), a marker of vascular inflammation, seems to predict vascular damage in patients with Type 2 diabetes. Beside the lipid-lowering effect, statins seem to slow the progression of atherosclerosis through a series of anti-inflammatory effects, including a reduction of sCD40L levels. This study compared the effect of a short-term (12 weeks) treatment with rosuvastatin or simvastatin on some markers of inflammation in 36 patients with Type 2 diabetes and moderate hypercholesterolemia. As expected, both drugs significantly modified lipid profile; moreover, rosuvastatin and simvastatin were both able to significantly reduce albumin excretion rate in these patients, without affecting urinary N-acetyl-beta-D-glucosaminidase. Serum homocysteine was not influenced by the treatment, as interleukin-6 levels, while C reactive protein diminished; moreover, rosuvastatin, but not simvastatin, was able to significantly reduce sCD40L. The only clinical parameter related with the variations in sCD40L was systolic blood pressure. In hypercholesterolemic Type 2 diabetic patients, sCD40L, a factor playing a pivotal role in the pathogenesis of atherosclerosis and associated with more rupture-prone lesions, is reduced by short-term treatment with rosuvastatin.

Biological consequences of statins in Candida species and possible implications for human health

The statins, simvastatin and atorvastatin are the most widely prescribed drugs. Statins lower cholesterol levels through their action on HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) reductase, an essential enzyme for the biosynthesis of cholesterol. Fungal HMG-CoA reductases are also inhibited by statins, resulting in reduced levels of ergosterol (the fungal equivalent of cholesterol) and concomitant growth inhibition. This effect occurs in a range of fungal species and possibly affects fungal colonization of people on statin therapy. Furthermore, it may suggest that statins could have a role in new antifungal therapies. Possibly associated with the reduction in ergosterol levels, statins also inhibit respiratory growth. In the yeast, Candida glabrata, passage with statins dramatically increased the frequencies of petite mutants that were devoid of mitochondrial DNA, suggesting that statins caused a defect in the maintenance of mitochondrial DNA. These observations in C. glabrata may provide further insights into side effects of statins in humans undergoing treatment for hypercholesterolaemia. In addition, C. glabrata may be highly useful for the preliminary screening of agents to reduce statin side effects.

Statins increase neurogenesis in the dentate gyrus, reduce delayed neuronal death in the hippocampal CA3 region, and improve spatial learning in rat after traumatic brain injury

Traumatic brain injury (TBI) remains a major public health problem globally. Presently, there is no way to restore cognitive deficits caused by TBI. In this study, we seek to evaluate the effect of statins (simvastatin and atorvastatin) on the spatial learning and neurogenesis in rats subjected to controlled cortical impact. Rats were treated with atorvastatin and simvastatin 1 day after TBI and daily for 14 days. Morris water maze tests were performed during weeks 2 and 5 after TBI. Bromodeoxyuridine (BrdU; 50 mg/kg) was intraperitoneally injected 1 day after TBI and daily for 14 days. Brain tissue was processed for immunohistochemical staining to identify newly generated cells and vessels. Our data show that (1) treatment of TBI with statins improves spatial learning on days 31-35 after onset of TBI; (2) in the non-neurogenic region of the hippocampal CA3 region, statin treatment reduces the neuronal loss after TBI, demonstrating the neuroprotective effect of statins; (3) in the neurogenic region of the dentate gyrus, treatment of TBI with statins enhances neurogenesis; (4) statin treatment augments TBI-induced angiogenesis; and (5) treatment with simvastatin at the same dose provides a therapeutic effect superior to treatment with atorvastatin. These results suggest that statins may be candidates for treatment of TBI.

Does the prevalence of nasal polyps increase in patients using statins?

Several statins inhibit T-helper 1 development and induce T-helper 2 polarization and production of T-helper 2 cytokines that promote the activation and chemotaxis of eosinophils. Whether statins promote the development of nasal polyps has so far been uncertain. No studies have evaluated the frequency of the development of nasal polyps in patients using statins. To better define the relationship of statin use to the presence of nasal polyps, the investigators explored the frequency of the development of nasal polyps in patients who were using statins. A total of 200 patients who were using statins and 200 who were not using statins (400 cases) were investigated. All patients were examined for nasal polyps by anterior rhinoscopy or investigation with a fiberoptic endoscope. In addition, immunoglobulin E levels were measured, a skin prick test was performed, and the results from the 2 groups were compared. Nasal polyps were detected in 4 subjects who were using statins, whereas 5 nasal polyps were found in the control group; differences between the 2 groups were statistically insignificant (P>.05). When the atopy status of the 2 groups was compared, prick test positivity and serum immunoglobulin E levels were found to be 15% and 44+/-31 IU/mL in the statin group and 19% and 68+/-23 IU/mL in the control group (P>.05). These results show that nasal polyposis is a multifactorial disease with several different causes; however, the frequency of the development of nasal polyps does not increase in patients who use statins.

A dose-specific meta-analysis of lipid changes in randomized controlled trials of atorvastatin and simvastatin

BACKGROUND

The available statins exhibit differences in the potency with which they alter serum lipid levels.

OBJECTIVE

Meta-analyses were conducted to assess the relative potency of atorvastatin and simvastatin (the 2 most commonly prescribed statins) across all possible dose combinations in terms of changes in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C).

METHODS

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, National Health Service (NHS) Centre for Reviews and Dissemination database, NHS Economic Evaluation Database, and Database of Abstracts of Reviews of Effects were searched for randomized, head-to-head trials of atorvastatin and simvastatin in patients aged >or=18 years with elevated levels of serum TC and LDL-C. Reference lists of the identified articles, letters, and editorials also were reviewed. The manufacturers of atorvastatin and simvastatin products were contacted for relevant unpublished data. All studies were reviewed and rated for quality by 2 independent reviewers. The maximum quality score was 4 points; trials with a score of <2 points were considered to be of poor quality and were excluded from analysis. Dose comparisons were abstracted in pairs from each trial. Meta-analyses were conducted on the fixed-dose pairs for each lipid parameter. Weighted mean differences in the change in TC, LDL-C, TG, and HDL-C were estimated using the Der Simonian and Laird random-effects model.

RESULTS

Seventeen published trials and 1 unpublished study were included in the meta-analyses. Atorvastatin treatment was associated with significantly greater reductions in TC, LDL-C, and TG in the majority of dose comparisons with simvastatin. The potency of atorvastatin and simvastatin was comparable at dose ratios between 1:2 and 1:4. Higher doses of simvastatin were more effective in increasing HDL-C levels than atorvastatin, with no apparent dose-equivalence point. The HDL-C advantage of simvastatin was greatest when simvastatin 80 mg was compared with atorvastatin 80 mg (weighted mean difference, -4.35%; 95% CI, -5.64 to -3.08, P < 0.001).

CONCLUSIONS

In these meta-analyses, atorvastatin was 2 to 4 times as potent as simvastatin in reducing TC, LDL-C, and TG, indicating that the dose equivalence of atorvastatin and simvastatin lay between 1:2 and 1:4. In contrast, simvastatin was more effective than atorvastatin in increasing HDL-C, but without any indication of a point of dose equivalence.

Low-density lipoprotein-dependent and -independent effects of cholesterol-lowering therapies on C-reactive protein: a meta-analysis

OBJECTIVES

This study sought to assess the contribution of low-density lipoprotein (LDL)-dependent and LDL-independent effects of LDL-lowering therapies to changes in C-reactive protein (CRP) in healthy or stable subjects.

BACKGROUND

Correlations of change in LDL and CRP in individuals are lowered by their measurement variability. By using average changes in LDL and CRP in study groups, meta-analysis reduces this variability to better assess their correlation.

METHODS

A systematic search for randomized placebo-controlled trials reporting change in LDL and CRP with LDL-lowering interventions retrieved 23 studies with 57 groups treated with a variety of statins, nonstatin drugs, or other regimens. Meta-analysis techniques assessed the relationships between average mean differences (placebo - treatment) in change in CRP and LDL.

RESULTS

The overall reduction in CRP was 28% (95% confidence interval 26% to 30%). Significantly greater CRP reduction occurred in statin and statin-ezetimibe interventions, interventions using 80 mg/day of statins, and with greater LDL lowering. Meta-regression analysis showed a strong correlation between the change in LDL and CRP (r = 0.80, p < 0.001). Statin therapies had no significant effect on CRP after adjusting for the change in LDL. In a multivariate model applied to a range of LDL reduction typically seen with statins (20% to 60%), 89% to 98% of CRP change was related to LDL lowering and 2% to 11% was related to non-LDL effects of statins.

CONCLUSIONS

In clinical practice, most of the anti-inflammatory effect of LDL-lowering therapies is related to the magnitude of change in LDL. The potential non-LDL effects of statins on inflammation are much smaller in magnitude.

Anti-inflammatory mechanism of simvastatin in mouse allergic asthma model

Statins have anti-inflammatory property and immunomodulatory activity. In this study we aimed to investigate the inhibitory mechanism of simvastatin in allergic asthmatic symptoms in mice. BALB/c mice were sensitized and challenged by ovalbumin to induce asthma. Ovalbumin-specific serum IgE levels were measured by enzyme-linked immunosorbent assay (ELISA), and the recruitment of inflammatory cells into bronchoalveolar lavage fluid or lung tissues was measured by Diff-Quik staining and hematoxylin and eosin (H&E) staining, respectively, the expressions of CD40, CD40 ligand (CD40L), and vascular cell adhesion molecule-1 (VCAM-1) by immunohistochemistry, the mRNA and protein expressions of cytokines in lung tissues by reverse transcriptase-polymerase chain reaction (RT-PCR) or ELISA, epithelial hyperplasia by periodic acid-Schiff (PAS) staining, activities of matrix metalloproteinases (MMPs) by zymography, the activities of small G proteins, mitogen-activated protein (MAP) kinases and nuclear factor-kappa B (NF-kappaB) in bronchoalveolar lavage cells and lung tissues by western blot and EMSA, respectively. Simvastatin reduced ovalbumin-specific IgE level, the number of total inflammatory cells, macrophages, neutrophils, and eosinophils into bronchoalveolar lavage fluid, the expressions of CD40, CD40L or VCAM-1, the mRNA and protein levels of interleukin (IL)-4, IL-13 and tumor necrosis factor (TNF)-alpha, the numbers of goblet cells, activities of MMPs, and further small G proteins, MAP kinases and NF-kappaB activities in bronchoalveolar lavage cells and lung tissues increased in ovalbumin-induced allergic asthma in mice. Our data suggest that simvastatin may be used as a therapeutic agent in asthma, based on reductions of various allergic responses via regulating small G proteins/MAP kinases/NF-kappaB in mouse allergic asthma.

Serum markers of vascular inflammation in dyslipemia

Atherosclerosis is widely recognized as an inflammatory disease because systemic and local inflammatory events mediate all phases of plaque development and progression. Basic and clinical studies have focused on identifying potentially useful markers of inflammation. In this article, we review the inflammatory pathogenesis of atherosclerosis, and highlight recent results of several of the more promising markers of inflammation for cardiovascular risk assessment. Of these markers, the most reliable and accessible for clinical use is currently high-sensitivity C-reactive protein (CRP). At present, most clinical guidelines do not recommend routine measurement of these inflammatory markers. However, these serum markers of vascular inflammation may be useful as an adjunct to lipid screening, especially for patients whose lipid values may not be severely elevated, but who are at intermediate risk according to scoring systems that take into account multiple established risk factors. In addition, since the pleiotropic effects of statins include the inhibition of inflammatory response, serum inflammatory markers could also be useful for monitoring this action. Nevertheless, several issues have to be evaluated before the measurements of inflammatory markers can be used for cardiovascular risk prediction in either clinical practice or in clinical trials evaluating anti-atherosclerotic drugs.

Cytokine Secretion via Cholesterol-rich Lipid Raft-associated SNAREs at the Phagocytic Cup

Lipopolysaccharide-activated macrophages rapidly synthesize and secrete tumor necrosis factor alpha (TNFalpha) to prime the immune system. Surface delivery of membrane carrying newly synthesized TNFalpha is controlled and limited by the level of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins syntaxin 4 and SNAP-23. Many functions in immune cells are coordinated from lipid rafts in the plasma membrane, and we investigated a possible role for lipid rafts in TNFalpha trafficking and secretion. TNFalpha surface delivery and secretion were found to be cholesterol-dependent. Upon macrophage activation, syntaxin 4 was recruited to cholesterol-dependent lipid rafts, whereas its regulatory protein, Munc18c, was excluded from the rafts. Syntaxin 4 in activated macrophages localized to discrete cholesterol-dependent puncta on the plasma membrane, particularly on filopodia. Imaging the early stages of TNFalpha surface distribution revealed these puncta to be the initial points of TNFalpha delivery. During the early stages of phagocytosis, syntaxin 4 was recruited to the phagocytic cup in a cholesterol-dependent manner. Insertion of VAMP3-positive recycling endosome membrane is required for efficient ingestion of a pathogen. Without this recruitment of syntaxin 4, it is not incorporated into the plasma membrane, and phagocytosis is greatly reduced. Thus, relocation of syntaxin 4 into lipid rafts in macrophages is a critical and rate-limiting step in initiating an effective immune response.

Other than potency, are all statins the same?

Statins have been shown to interact with metabolic pathways that potentially affect physiologic functions beyond cholesterol balance. We may broadly categorize non-lipid effects of statins as clinically favorable or clinically detrimental. Whether non-lipid effects of statins are of clinical significance and whether there are differences in non-lipid effects among statins remain points of major current controversy. This review evaluates the available information on potential differences among statins in non-lipid effects.

Is atrial fibrillation an inflammatory disorder?

There is mounting evidence to support the influence of inflammation in the pathogenesis of atrial fibrillation (AF). Indeed, AF is associated with increased levels of known inflammatory markers, even after adjustment for confounding factors. The renin-angiotensin-aldosterone system (RAAS) appears to play a key role in this process. Atrial biopsies from patients with AF have also confirmed the presence of inflammation. Furthermore, there is preliminary evidence to support a number of drug therapies that have the potential to reduce the clinical burden of AF. In this review, we present an overview of the evidence supporting a link between inflammation and AF, and some of the drug therapies, such as the angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, steroids, fish oils, and vitamin C, that might be efficacious in the prevention of AF by modulating inflammatory pathways.

Impact of simvastatin on hemostatic and fibrinolytic regulators in Type 2 diabetes mellitus

Simvastatin, a widely used 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, effectively reduced cardiac death and ischemic events in patients with coronary heart disease (CHD) and diabetes mellitus (DM). The mechanism of cardiovascular benefits of statins in DM remains unclear. We examined how simvastatin influences the levels of several in vivo markers for coagulation and fibrinolysis in 26 Type 2 DM patients. The diabetic patients received 20 mg/day of simvastatin up to 12 months. The levels of total cholesterol (TC), low density lipoprotein-cholesterol (LDL-c) and triglycerides in peripheral circulation of patients were significantly reduced after > or =6 weeks of simvastatin treatment. Levels of prothrombin fragment 1+2 (F1+2), factor VII, plasminogen activator inhibitor-1 (PAI-1) and tissue factor pathway inhibitor (TFPI) antigens, but not tissue plasminogen activator (tPA) antigen, in the pre-simvastatin plasmas of the diabetic patients were significantly higher than the levels found in plasmas of healthy subjects. Significant reductions in F1+2 and PAI-1 levels were evident > or =6 weeks after the diabetic patients received simvastatin. Levels of total tPA, TFPI, FVII, hemoglobin A1c, fasting blood glucose, and insulin in the diabetic patients' plasma were not significantly altered by simvastatin treatment. Positive correlations were found between PAI-1 versus TC, PAI-1 versus LDL-c, and FVII versus triglycerides in the plasmas of simvastatin-treated patients. The results suggest that simvastatin reduces in vivo prothrombinase activity and PAI-1 levels in type 2 DM patients. These actions may contribute to the protective properties of simvastatin against ischemic events in diabetic patients.

Hyperlipidemia in children

Hyperlipidemia in children has emerged as an increasingly prevalent risk factor in children, concomitant with the worldwide epidemic of obesity. Hyperlipidemia can alter vascular endothelial function and impair some of its pro-fibrinolytic and anti-thrombotic regulatory properties, as well as initiate the atherosclerotic process. There are strong links between vascular changes and hyperlipidemia in children, both from pathologic and non-invasive assessment studies. More severe lipid abnormalities in children are related to primary familial dyslipidemias. Current recommendations for screening begin with assessment of family history for cardiovascular disease or events or parental hyperlipidemia. High-risk individuals merit more intensive investigation and intervention. While fat-restricted diets have been shown to be safe in children, lipid-lowering is modest. Those with more severe lipid abnormalities may meet criteria for drug therapy, and the statin agents commonly used in adults are increasingly being used in high-risk children, with similar efficacy and safety, although long-term concerns remain.

Statins and Blood Coagulation

The 3-hydroxy-3-methylglutaryl (HMG)-coenzyme A (CoA) reductase inhibitors (statins) have been shown to exhibit several vascular protective effects, including antithrombotic properties, that are not related to changes in lipid profile. There is growing evidence that treatment with statins can lead to a significant downregulation of the blood coagulation cascade, most probably as a result of decreased tissue factor expression, which leads to reduced thrombin generation. Accordingly, statin use has been associated with impairment of several coagulant reactions catalyzed by this enzyme. Moreover, evidence indicates that statins, via increased thrombomodulin expression on endothelial cells, may enhance the activity of the protein C anticoagulant pathway. Most of the antithrombotic effects of statins are attributed to the inhibition of isoprenylation of signaling proteins. These novel properties of statins, suggesting that these drugs might act as mild anticoagulants, may explain, at least in part, the therapeutic benefits observed in a wide spectrum of patients with varying cholesterol levels, including subjects with acute coronary events. The HMG-CoA reductase inhibitors (statins) have been shown to exhibit several vascular protective effects, including antithrombotic properties, that are not related to changes in lipid profile. Treatment with statins can lead to a significant downregulation of the blood coagulation cascade, most probably as a result of decreased tissue factor expression, which leads to reduced thrombin generation.

Delayed Thrombosis after Traumatic Brain Injury in Rats

Secondary thrombosis may contribute to cerebral ischemia caused by traumatic brain injury (TBI). In this study, we sought to investigate the temporal and spatial profiles of intravascular thrombosis and to evaluate the effect of atorvastatin, a beta-hydroxy-beta-methylglutaryl coenzyme-A (HMG-CoA) reductase inhibitor, on thrombosis after TBI. Young male Wistar rats weighing 350-400 g were subjected to controlled cortical impact injury, and were sacrificed at 1 and 4 h, and 1, 3, 8, and 15 days after TBI (5 rats/time point), respectively. For the evaluation of the effects of atorvastatin on intravascular thrombosis, rats were subjected to TBI, and subsequently atorvastatin (1 mg/kg) was orally administered starting 1 day after TBI and then daily until sacrifice at 3, 8, and 15 days after TBI (5 rats/time point). Before sacrifice of animals, blood was withdrawn and employed for the measurement of von Willibrand factor and platelet activity using enzyme-linked immunoabsorbant assay (ELISA). Brain tissues were prepared for histological analysis. The data show that (1) delayed thrombosis is present in the lesion boundary zone and in the hippocampal CA3 region, starting at 1-4 h, peaking at 1-3 days, and then declining at 8 and 15 days after TBI; (2) intravascular thrombosis also occurs in the other areas of cortex, striatum, and corpus callosum, but with a scattered distribution; (3) delayed thrombi are composed of platelets, fibrin, and vWF; and (4) reduction of the plasma vWF level and platelet activity by atorvastatin decreases delayed thrombosis after TBI. These data suggest that atorvastatin reduces intravascular thrombosis attributed to hemostatic disturbances caused by TBI.

Beneficial cardiovascular pleiotropic effects of statins

Pleiotropic effects of a drug are actions other than those for which the agent was specifically developed. These effects may be related or unrelated to the primary mechanism of action of the drug, and they are usually unanticipated. Pleiotropic effects may be undesirable (such as side effects or toxicity), neutral, or, as is especially the case with HMG-CoA reductase inhibitors (statins), beneficial. Pleiotropic effects of statins include improvement of endothelial dysfunction, increased nitric oxide bioavailability, antioxidant properties, inhibition of inflammatory responses, and stabilization of atherosclerotic plaques. These and several other emergent properties could act in concert with the potent low-density lipoprotein cholesterol-lowering effects of statins to exert early as well as lasting cardiovascular protective effects. Understanding the pleiotropic effects of statins is important to optimize their use in treatment and prevention of cardiovascular disease.

Modulatory effects of HMG-CoA reductase inhibitors in diabetic microangiopathy

3-hydroxy-3-methyl-glutaryl CoA (HMG-CoA) reductase inhibitors or statins are competitive inhibitors of the rate-limiting enzyme in cholesterol biosynthesis. Several large landmark clinical studies have shown a marked reduction of cardiovascular mortality and morbidity in patients treated with statins. Because of the strong association between serum cholesterol levels and coronary artery disease, investigators initially assumed that the predominant beneficial effects of statins result from their lipid-lowering properties. However, more recent observations have suggested that the clinical benefits of statins may be in part independent of their cholesterol-lowering effects. The pleiotropic or cholesterol-independent effects of statins might result from preventing the production of isoprenoids. Isoprenoids serve as important lipid attachments for the post-translational modification of a variety of proteins such as small GTP binding proteins implicated in intracellular signaling. The list of different pleiotropic effects of statins is still growing and, among others, includes the modulatory effects of statins on endothelial function, oxidative stress, coagulation, plaque stability, and inflammation. The pleiotropic effects of statins represent an area of great interest in prevention and therapy of cardiovascular and other chronic diseases. An area of particular interest is the potential beneficial effects of statins in diabetes and its micro/macrovascular complications. This review summarizes our current understanding of the pleiotropic effects of statins in diabetes and the modulatory effects of statins in various pathobiological pathways involved in diabetes and its complications.

Effects of conventional and aggressive statin treatment on markers of endothelial function and inflammation

BACKGROUND

Atherosclerosis is considered to be a chronic inflammatory disorder. Several large-scale clinical studies demonstrate that markers of inflammation, such as high-sensitivity C-reactive protein (hsCRP), fibrinogen, and soluble CD40 ligand, are potent and independent predictors of vascular risk.

HYPOTHESIS

The study was undertaken to investigate the effect of increasing the statin dose from conventional to aggressive treatment on lipids levels, inflammation, and endothelial function in patients with coronary artery disease (CAD).

METHODS

We randomized 97 patients to either 20 mg simvastatin or 80 mg atorvastatin. Plasma levels of lipids, hsCRP, fibrinogen, soluble adhesion molecules, and nitric oxide-total were analyzed at baseline and after 6 months of treatment.

RESULTS

Lipid values were significantly reduced in both treatment groups, but with significantly greater reduction in the aggressively treated group. Furthermore, aggressive statin treatment significantly decreased hsCRP and fibrinogen, while only small reductions were seen in the conventionally treated group, resulting in significant differences between the two treatment groups (p < 0.001). Nitric oxide-total increased significantly in both treatment groups, although the increase was more pronounced in the aggressively treated group (22.6 vs. 15.6%).

CONCLUSION

Aggressive statin treatment significantly improved lipid status and reduced markers of inflammation and improved endothelial function compared with conventional treatment in patients with CAD. No interaction was observed, and high-dose treatment did not offer additional benefit compared with standard-dose treatment with respect to soluble adhesion molecules.