High-dose Simvastatin Research Articles

Atheroprotective lipoprotein effects of a niacin-simvastatin combination compared to low- and high-dose simvastatin monotherapy

Niacin has multiple lipoprotein effects that may provide cardiovascular benefit when added to statin monotherapy. In this randomized, placebo-controlled trial (n = 75) of magnetic resonance imaging of carotid atherosclerosis, we performed a secondary comparison of combination niacin-statin (simvastatin 20 mg/Niacin-ER 2G [S20/N]) to monotherapy with moderate (20 mg [S20]) and high-dose (80 mg [S80]) simvastatin on lipids, apolipoproteins (apo), low density lipoprotein (LDL) and high density lipoprotein (HDL) particle subclasses, and inflammatory markers. At baseline, average age was 71, 72% were male, 62.5% used statins, and average LDL-cholesterol was 111 mg/dL. At 12 months, S20/N, compared to S80, significantly reduced apoB (-36.6% vs -11.9%; P = .05) and lipoprotein(a) (-18% vs +3.5%; P = .001) and had at least an equivalent effect on LDL-cholesterol (-39.3% vs -24.3%; P = .24). The combination reduced the proportion of subjects with atherogenic LDL pattern-B (50% to 11.5%) compared to S80 (56% to 56%) (P = .01). Despite increases in plasma free fatty acids (+62.4%; F = 5.65, P = .005 vs S20 and S80), plasma triglycerides (-29.4%; F = 6.88, P = .002 vs S20 and S80), and very-low-density lipoprotein (-44.2%; F = 7.94, P < .001 vs S20 and S80), levels were reduced by S20/N. S20/N increased HDL-cholesterol levels (+18.1%) as compared to S20 (0%) and S80 (+5.9%) (P < .001 vs both statin arms), largely due to an increase in HDL particle size (+4.6%; P = .01 vs both statin arms). We demonstrate that full-dose niacin/moderate-dose simvastatin combination has sustained benefits on atherogenic apoB lipoproteins, at least comparable to high-dose simvastatin, while also raising HDL-cholesterol. Results of large clinical trials will inform whether niacin-statin combinations reduce cardiovascular disease events.

Effects of the combination with α‐tricalcium phosphate and simvastatin on bone regeneration

Although local application of statins stimulates bone formation, high dose of simvastatin induces inflammation. A study was conducted to test the hypothesis that maximum bone regeneration with less inflammation would be achieved by combining an optimal dose of simvastatin with alpha-tricalcium phosphate (alpha-TCP), which is an osteoconductive biomaterial capable of releasing the drug gradually. Bilateral 5-mm-diameter calvarial defects were created in adult Wistar rats and filled with preparations of different doses of simvastatin (0, 0.01, 0.1, 0.25 and 0.5 mg) combined with alpha-TCP particles or left empty. The animals were sacrificed at 2, 4 and 8 weeks and analyzed radiologically and histologically. Half of the animals of 4 and 8 weeks were labeled with fluorescence dyes and histomorphometrically analyzed. Simvastatin doses of 0.25 and 0.5 mg caused inflammation of the soft tissue at the graft site whereas control and other doses did not. The micro-CT analysis revealed that the alpha-TCP with 0.1 mg simvastatin (TCP-0.1) group yielded significantly higher bone volumes than untreated control group at all three time points (249%, 227% and 266% at 2, 4 and 8 weeks, respectively). The percentage of defect closure, bone mineral content and bone mineral density were also higher in the TCP-0.1 group than in the other groups. When combined with alpha-TCP particles, 0.1 mg simvastatin is the optimal dose for stimulation of the maximum bone regeneration in rat calvarial defects without inducing inflammation and it could be applied as an effective bone graft material.

Determination of Simvastatin Induced Variations in Sciatic Nerve by ATR-FTIR Spectroscopy

Simvastatin, a lipophilic statin derived drug, is commonly used drug for treating lipid and cardiovascular disorders. It is well known that the long term usage of this drug leads to peripheral neuropathy, mononeuropathy and memory problems. Moreover a possible treating agent in central nervous system disease like Alzheimer has been reported. The results that were obtained from simvastatin and nervous system are clinically unclear and controversial. Therefore the current study was aimed to clarify the possible effects of simvastatin on the content, composition, dynamics and conformation of macromolecules in rat sciatic nerve using ATR-FTIR Spectroscopy. Experimental male adult rats were divided two groups as control (n=10) and simvastatin-treated group (n=10). 50 mg simvastatin/ kg was given to treated group by oral gavage for 1 month. In the FTIR spectra, the shift in peak positions, the change in bandwidths and the intensity/area values of the bands were determined and compared in between control and treated groups. The results revealed that there is a significant decrease in amount of unsaturated lipid in simvastatin treated sciatic nerve, which indicates an increase in lipid peroxidation. Moreover, with simvastatin treatment a reduction in the saturated lipid, protein, glycogen and nucleic acid content was found showing degradation or decrease in the synthesis of these molecules. Protein secondary structure was found to be changed as a decrease in α-helix and β-sheet content and an increase aggregated β-sheet and random coil content in treated samples implying protein denaturation. The outcomes of this study show that high dose simvastatin application leads to structural and molecular variations in sciatic nerve by affecting its macromolecular composition.Keywords: sciatic nerve, simvastatin, statin, ATR-FTIR spectroscopy, protein secondary structure.

No effect of lipid lowering on platelet activity in patients with coronary artery disease and type 2 diabetes or impaired glucose tolerance

In addition to lowering cholesterol, statins may reduce platelet activity and exert beneficial non-lipid (pleiotropic) effects. We evaluated the effects of two different simvastatin based treatment regimens on platelet reactivity in patients with dysglycemia and coronary artery disease (CAD). Thirty-two patients with type 2 diabetes or impaired glucose tolerance and stable CAD received six weeks of double-blind treatment with simvastatin 80 mg daily (S80; n = 16) or ezetimibe 10 mg and simvastatin 10 mg daily (E10/S10; n = 16). Total and low-density lipoprotein (LDL) cholesterol, and high sensitivity C-reactive protein (CRP) decreased similarly in the two groups. LDL (mM) decreased from 3.2 +/- 0.6 to 1.7 +/- 0.7 with E10/S10 and from 3.0 +/- 1.0 to 1.4 +/- 0.5 with S80 treatment. Platelet function was evaluated by whole blood flow cytometry and turbidimetric aggregometry with agonist stimulation ex vivo before and after treatment. Neither treatment affected basal or adenosine diphosphate (ADP)- or thrombin-induced platelet P-selectin expression, or fibrinogen binding, or platelet-leukocyte aggregation. Similarly, neither treatment affected ADP-induced platelet aggregation. In conclusion, lipid lowering treatment with high dose simvastatin or low dose simvastatin plus ezetimibe did not exert any substantial inhibitory effects on the basal or agonist-stimulated activity of circulating platelets in patients with stable CAD and type 2 diabetes or impaired glucose tolerance.

Dose-Specific Biphasic Effects of Simvastatin on the Expression of CXCL10 and CX3CL1 by Human Osteoblasts

Objective To better understand the effects of simvastatin (SS) on the expression and secretion of two chemokines, CXCL10 and CX3CL1, by osteoblasts, and to test whether inhibition of isoprenoid intermediates of cholesterol biosynthesis were involved in the effects of SS. Methods Human osteoblasts were incubated in the presence or absence of the inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ), with and without SS (0.1–100 μM). Culture supernatants were then collected, and expression of CXCL10 and CX3CL1 mRNA in osteoblasts was examined using quantitative TaqMan real-time polymerase chain reaction. The levels of CXCL10 and CX3CL1 were measured using enzyme-linked immunosorbent assays. Results At a high concentration (100 μM), SS inhibited expression and secretion of the chemokines and showed cytotoxity, whereas at lower concentrations (0.1–1 μM) SS stimulated the expression and secretion of the chemokines. Expression and secretion of CXCL10 or CX3CL1 from osteoblasts were induced by stimulation with TNF-α and IFN-γ. In addition, SS exerted a biphasic effect on the evoked induction of CXCL10 and CX3CL1. Chemokine expression and secretion was also assayed in the presence of mevalonate (MEV), geranylgeranyl pyrophosphate (GGPP) or farnesyl pyrophosphate (FPP). MEV abolished both the inhibitory effect of high-dose SS and the stimulatory effect of low-dose SS. On the other hand, GGPP abolished only the inhibitory effects of high-dose SS, and FPP had no effect at all. Conclusions These findings suggest that osteoblasts are an important cellular source of CXCL10 and CX3CL1, and that statins such as SS may modulate the inflammatory process in bone tissues to inhibit bone resorption and stimulate bone formation through biphasic modulation chemokine synthesis.

Vigilance Needed in Recognizing Behavior Changes in Patients Taking Statins

Sir: Evidence from randomized trials suggests that statins are very safe.1 Consequently, their widespread use is highly promoted, even in high doses, and among adults of all ages. However, we feel caution is warranted, particularly when striving for aggressive low-density lipoprotein (LDL) cholesterol targets. In general, subjects in statin trials have been free of many chronic diseases, such as prevalent cancer, severe renal impairment, and neurodegenerative and depressive disorders. In clinical practice, individuals with the aforementioned problems and other chronic ailments are commonly treated with statins to achieve LDL cholesterol–lowering targets. Hence, it is sometimes dangerous to extrapolate trial results to real-world practice. High-dose simvastatin alters cholesterol turnover in the brain.2 Low-dose simvastatin has caused significant decreases in positive affect in elderly volunteers.3 Additionally, violent behavior has been associated with hypocholesterolemia resulting from a novel apolipoprotein B gene mutation.4 Furthermore, victims of violent suicides were found to have lower frontal cortex gray-matter cholesterol content than victims of nonviolent suicides.5 Statins were introduced in 1987. During the 1990s, in Scotland, there was a sharp increase in antidepressant prescribing by physicians.6 It is certainly plausible that the increase in the use of antidepressants might have occurred as a result of statin- induced lower cholesterol levels, leading to more depression. As the prescribing of statins becomes more widespread and cholesterol-lowering goals more aggressive, practicing clinicians must be vigilant in recognizing behavior changes, particularly in elderly and depressed individuals. Mark R. Goldstein, M.D. Private Practice, Bonita Springs, Florida Luca Mascitelli, M.D. Medical Service, “Julia” Alpine Brigade, HQ, Udine, Italy Francesca Pezzetta, M.D. Cardiology Department, Hospital of Tolmezzo, Tolmezzo, Italy

High dose of simvastatin induces hyperlocomotive and anxiolytic-like activities: The association with the up-regulation of NMDA receptor binding in the rat brain

Statins are widely being used for the treatment of a variety of conditions beyond their original indication for lowering cholesterol. We have previously reported that simvastatin affected the dopaminergic system in the rat brain. This study aims to investigate locomotor and anxiety effects along with the regional changes of N-methyl- d-aspartate (NMDA) receptors in the rat brain after 4-week administration of simvastatin. Hyperlocomotive and anxiolytic-like activities in the rat were observed after chronic administration of high dose simvastatin (10 mg/kg/day). Distributions and alterations of NMDA receptors in the post-mortem rat brain were detected by [ 3H] MK-801 binding autoradiography. Simvastatin increased [ 3H] MK-801 binding, predominantly in the prefrontal cortex (20%, p = 0.003), primary motor cortex (20%, p < 0.001), cingulate cortex (28%, p < 0.001), hippocampus (41%, p < 0.001), caudate putamen (30%, p = 0.029), nucleus accumbens (27%, p = 0.035) and amygdala (45%, p < 0.001) compared to controls. Significant positive correlations were identified between hyperlocomotive as well as anxiolytic-like activities and the upregulation of NMDA receptors in different brain regions. Our results also provide strong evidence that chronic high dose simvastatin administration is to exhibit NMDA antagonist-like effects, which would partially explain the anxiolytic and hyperlocomotor activities. These findings contribute to a better understanding of the critical roles of simvastatin in modulating psycho-neurodegenerative disorders, via NMDA receptors.

Primary Prevention and Statins: Is It Just About Going to Class?

Primary Prevention and Statins: Is It Just About Going to Class?

Is Carotid Intima-Media Thickness a Reliable Clinical Predictor?

Is Carotid Intima-Media Thickness a Reliable Clinical Predictor?

Effects of High-Dose Simvastatin Therapy on Glucose Metabolism and Ectopic Lipid Deposition in Nonobese Type 2 Diabetic Patients

OBJECTIVE—Statins may exert pleiotropic effects on insulin action that are still controversial. We assessed effects of high-dose simvastatin therapy on peripheral and hepatic insulin sensitivity, as well as on ectopic lipid deposition in patients with hypercholesterolemia and type 2 diabetes.RESEARCH DESIGN AND METHODS—We performed a randomized, double-blind, placebo-controlled, single-center study. Twenty patients with type 2 diabetes received 80 mg simvastatin (BMI 29 ± 4 kg/m2, age 55 ± 6 years) or placebo (BMI 27 ± 4 kg/m2, age 58 ± 8 years) daily for 8 weeks and were compared with 10 healthy humans (control subjects; BMI 27 ± 4 kg/m2, age 55 ± 7 years). Euglycemic-hyperinsulinemic clamp tests combined with d-[6,6-d2]glucose infusion were used to assess insulin sensitivity (M) and endogenous glucose production (EGP). 1H magnetic resonance spectroscopy was used to quantify intramyocellular and hepatocellular lipids.RESULTS—High-dose simvastatin treatment lowered plasma total and LDL cholesterol levels by ∼33 and ∼48% (P < 0.005) but did not affect M, intracellular lipid deposition in soleus and tibialis anterior muscles and liver, or basal and insulin-suppressed EGP. In simvastatin-treated patients, changes in LDL cholesterol related negatively to changes in M (r = −0.796, P < 0.01). Changes in fasting free fatty acids (FFAs) related negatively to changes in M (r = −0.840, P < 0.01) and positively to plasma retinol-binding protein-4 (r = 0.782, P = 0.008).CONCLUSIONS—High-dose simvastatin treatment has no direct effects on whole-body or tissue-specific insulin action and ectopic lipid deposition. A reduction in plasma FFAs probably mediates alterations in insulin sensitivity in vivo.

Abstract 1927: High-dose Simvastatin Alone Inhibits Rho Kinase and Improves Flow-mediated Vasodilatation to a Greater Extent than Combination of Low-dose Simvastatin and Ezetimibe, Despite Comparable Lipid-Lowering

Background: By inhibiting HMG-CoA reductase, statins not only inhibit cholesterol biosynthesis, but also decrease the formation of isoprenoids, which are important for mediating signaling through the Rho/Rho kinase (ROCK) pathway. In animal studies, inhibition of ROCK by statins improves endothelial function, decreases inflammation, and prevents atherosclerosis. These so-called cholesterol-independent effects of statins are dose-related and may contribute to some of their clinical benefits. We hypothesize that ezetimibe, which inhibits cholesterol absorption, does not exert these cholesterol-independent effects in humans. Methods and Results: We studied 60 dyslipidemia subjects (n=20 in each arm) in a prospective, randomized, observer-blinded study comparing treatment with simvastatin 40 mg/d or simvastatin/ezetimibe 10/10 mg/d to corresponding placebo tablets for 28 days. Prior statin usage was comparable between the groups and a washout period of 2 weeks was instituted before enrollment. Blood samples for fasting lipids, leukocyte ROCK activity and C-reactive protein (CRP) were collected at days 0 and 28. Baseline demographics, lipid levels, ROCK activity and CRP were not different between the 3 groups. Compared to placebo group, both treatment regimens decreased low-density lipoprotein cholesterol (LDL-C) by 38% and CRP by 32– 42% after 28 days (p&lt;0.001 for both compared to placebo). Although LDL-C and CRP were reduced to comparable levels by either lipid-lowering regimen (p&gt;0.05 between the groups), only simvastatin 40 mg reduced ROCK activity and improved forearm flow-mediated vasodilatation (FMD) (p&lt;0.01 for both compared to baseline). The reduction of ROCK activity with simvastatin 40 mg remained significant even after controlling for changes in LDL-C (p=0.01) and correlated with improvement in FMD (R 2 =0.78, p&lt;0.01). However, there was no correlation between changes in FMD with changes in LDL-C or CRP. Conclusions: These findings suggest that despite comparable decrease in LDL-C and CRP, high-dose statin monotherapy has greater effects on both ROCK activity and endothelial function than low-dose statin and ezetimibe. These findings provide additional evidence of potential statin benefits beyond cholesterol lowering.

Simvastatin attenuates bleomycin-induced pulmonary fibrosis in mice

Bleomycin-induced fibrosis is extensively used to model aspects of the pathogenesis of interstitial pulmonary fibrosis. This study aimed to determine the benefic effects and mechanisms of simvastatin on bleomycin-induced pulmonary fibrosis in mice. Bleomycin-induced pulmonary fibrosis mice were administered with simvastatin in different doses for 28 days. We measured inflammatory response, fibrogenic cytokines and profibrogenic markers in both bleomycin-stimulated and control lungs, and correlated these parameters with pulmonary fibrosis. Simvastatin attenuated the histopathological change of bleomycin-induced pulmonary fibrosis and prevented the increase of lung hydroxyproline content and collagen (I and III) mRNA expression induced by bleomycin. Moreover, simvastatin down-regulated the increased expression of transforming growth factor-beta1 (TGF-beta1) and connective tissue growth factor (CTGF) induced by bleomycin at both gene and protein levels. Simultaneously, the accumulation of neutrophils and lymphocytes and the increased production of tumor necrosis factor-alpha (TNF-alpha) in bronchial alveolar lavage fluid were inhibited by simvastatin in early inflammatory phase after bleomycin infusion. The higher dose of simvastatin was associated with a more significant reduction in these inflammatory and fibrotic parameters. Furthermore, the inactivation of p38, RhoA and Smad2/3 signaling pathways was observed during simvastatin administration. Simvastatin attenuated bleomycin-induced pulmonary fibrosis, as indicated by decreases in Ashcroft score and lung collagen accumulation. The inhibitory effect of simvastatin on the progression of pulmonary fibrosis may be demonstrated by reducing inflammatory response and production of TGF-beta1 and CTGF. These findings indicate that simvastatin may be used in the treatment of pulmonary fibrosis.

Simvastatin attenuates lipopolysaccharide-induced airway mucus hypersecretion in rats

Mucus hypersecretion in the respiratory tract and goblet cell metaplasia in the airway epithelium contribute to the morbidity and mortality associated with airway inflammatory diseases. This study aimed to examine the effect and mechanisms of simvastatin on airway mucus hypersecretion in rats treated with lipopolysaccharide (LPS). Mucus hypersecretion in rat airways was induced by intra-tracheal instillation of LPS. Rats treated with or without LPS were administered intra-peritoneally simvastatin (5 and 20 mg/kg) for 4 days. Expression of Muc5ac, RhoA and mitogen-activated protein kinases (MAPK) p38 in lung were detected by real-time polymerase chain reaction (PCR), immunohistochemistry or Western blotting. Tumor necrosis factor (TNF)-alpha and IL-8 in bronchoalveolar lavage fluid (BALF) were assayed by an enzyme-linked lectin assay and enzyme linked immunosorbent assay (ELISA). Simvastatin attenuated LPS-induced goblet cell hyperplasia in bronchial epithelium and Muc5ac hypersecretion at both the gene and protein levels in lung (P <0.05). Moreover, simvastatin inhibited neutrophil accumulation and the increased concentration of TNF-alpha and IL-8 in BALF follows LPS stimulation (P < 0.05). The higher dose of simvastatin was associated with a more significant reduction in Muc5ac mRNA expression, neutrophil accumulation and inflammatory cytokine release. Simultaneously, the increased expression of RhoA and p38 MAPK were observed in LPS-treated lung (P <0.05). Simvastatin inhibited the expression of RhoA and p38 phosphorylation in lung following LPS stimulation (P < 0.05). However, the increased expression of p38 protein in LPS-treated lung was not affected by simvastatin administration. Simvastatin attenuates airway mucus hypersecretion and pulmonary inflammatory damage induced by LPS. The inhibitory effect of simvastatin on airway mucus hypersecretion may be through, at least in part, the suppression of neutrophil accumulation and inflammatory cytokine release via inactivation of RhoA and p38 signaling pathway.

Simvastatin inhibits cell cycle progression in glucose-stimulated proliferation of aortic vascular smooth muscle cells by up-regulating cyclin dependent kinase inhibitors and p53

Simvastatin was reported to attenuate platelet-derived growth factor (PDGF)-induced vascular smooth muscle proliferation by up-regulation of cyclin dependent kinase (CDK) inhibitor p27, but had no effect on p16, p21, p53 expression. We investigate the mechanisms by which simvastatin inhibits vascular smooth muscle cell (VSMC) growth in high glucose conditions to mimic diabetes. Simvastatin was added to A7r5 cells cultured in high glucose (25 mM) medium, mimicking diabetes. We used an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to evaluate cell viability; flow cytometric analysis for cell counts distribution in the cell cycle; and Western blot, immunoblotting, and immunoprecipitation analyses to evaluate the effects of simvastatin on CDK activity and cell cycle regulatory proteins. Cell counts were significantly increased in G0/G1 phase and significantly decreased in S and G2/M phases. In our study, low dose of simvastatin had no significant inhibitory effect on VSMC growth in normal glucose condition. However, both low and high doses of simvastatin inhibited VSMC growth significantly in a dose-dependent manner in high glucose status. We also found that simvastatin inhibited phosphorylation of Rb, promoted expression of p53, p16, p21, p27 and decreased CDK2/4 activity. In conclusion, simvastatin inhibits VSMC proliferation in high glucose status, mimicking diabetes, inducing a G0/G1 phase cell cycle growth arrest by acting on multiple steps upstream of pRb, including inhibition of CDK2/4 expression and up-regulation of p53, p21, p16, and p27. We propose that statins may be used more extensively in diabetic patients regardless of lipid status for preventing atherosclerosis and restenosis after PCI.

High-dose statin use does not impair aerobic capacity or skeletal muscle function in older adults

3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) are lipid-lowering agents widely employed for atherosclerosis prevention. HMG-CoA reductase blockade reduces skeletal muscle coenzyme Q(10) (CoQ(10)) levels and mitochondrial respiratory chain activities and may produce mild to severe skeletal muscle myopathy. This study investigated whether high-dose statin treatment would result in measurably decreased exercise capacity in older men and women. Maximal oxygen consumption, aerobic endurance, oxygen uptake kinetics, maximal strength, muscular power, and muscular endurance were measured before and after 12 weeks of statin treatment (simvastatin, 80 mg/day) in nine men and one woman, ages 55-76 years, with LDL-cholesterol levels >3.3 mmol/l (mean = 4.2 +/- 0.2 mmol/l). Myalgia symptoms were assessed every 4 weeks. As expected, statin treatment resulted in significant decreases in LDL- and total-cholesterol levels (P < 0.01) with no significant changes in HDL-cholesterol or triglyceride levels. No significant changes were observed in aerobic capacity, endurance, oxygen kinetics or any measures of muscle function. No subject reported symptoms of myalgia, cramps, or weakness during the study. In the absence of myalgia or myopathic symptoms, high-dose simvastatin treatment did not impair exercise capacity in hyperlipidemic older individuals. We conclude that decreases in intramuscular CoQ(10), in most patients on high dose statin treatment may not be clinically relevant, due to inter-individual variability in the degree of CoQ(10) depletion, sensitivity of muscle to decreases in CoQ(10), or both.

The Effects of Low-Dose Simvastatin and Ezetimibe Compared to High-Dose Simvastatin Alone on Post-Fat Load Endothelial Function in Patients With Metabolic Syndrome: A Randomized Double-Blind Crossover Trial

Insulin resistance is associated with postprandial hyperlipidemia and endothelial dysfunction. Patients with metabolic syndrome, characterized by insulin resistance, are at increased cardiovascular risk. The aim of the present study was to investigate whether a similar low-density lipoprotein cholesterol (LDL-c) reduction with combination therapy of low-dose simvastatin and ezetimibe or with high-dose simvastatin alone has similar effects on (post-fat load) endothelial function. Randomized, double blind, crossover trial in 19 male obese patients with metabolic syndrome with high-dose simvastatin 80 mg versus combination therapy of low-dose simvastatin 10 mg with ezetimibe 10 mg. Fasting and post-fat load lipids and endothelial function (brachial artery flow-mediated dilation) were determined. Fasting LDL-c concentrations (2.1 +/- 0.5 mmol/L) and fasting endothelial function (6.9 +/- 0.8 vs. 7.6 +/- 1.2%) were the same after both treatments. Although post-fat load plasma triglycerides concentrations were higher (3.2 +/- 0.4 vs. 2.6 +/- 0.2 mmol x h/L) with combination therapy compared to monotherapy, ApoB particles were comparable (0.9 +/- 3.3 vs. -0.2 +/- 2.3 g x h/L). Combination therapy did not decrease post-fat load endothelial function (7.6 +/- 1.2 vs. 7.7 +/- 1.6%), contrary to high-dose simvastatin monotherapy (6.9 +/- 0.8 vs. 4.3 +/- 0.6%). Combination therapy with low-dose simvastatin and ezetimibe preserved post-fat load endothelial function, contrary to treatment with high-dose simvastatin monotherapy in male metabolic syndrome patients. There were no differences in fasting lipid profiles and endothelial function.

A phase II clinical trial does not show that high dose simvastatin has beneficial effect on markers of bone turnover in multiple myeloma

Several studies have evaluated the impact of low dose statin (20-80 mg/day) on bone metabolism with inconclusive results despite promising data of preclinical studies. In this study, we investigated the effect of high dose simvastatin (HD-Sim) on biochemical markers of bone turnover and disease activity in six heavily pretreated patients with multiple myeloma (MM). These patients were treated with simvastatin (15 mg/kg/day) for 7 days followed by a rest period of 21 days in two 4-week cycles. Endpoints were changes in the level of biochemical markers of (i) osteoclast activity (tartrate resistant acid phosphatase, TRACP); (ii) bone resorption (collagen fragments CTX and NTX); (iii) bone formation (osteocalcin and aminoterminal propeptide of type I collagen PINP); (iv) cholesterol; (v) regulators of bone metabolism [osteoprotegerin (OPG) and Dickkopf-1 (DKK-1)] and (vi) disease activity (monoclonal proteins or free light chains in serum). TRACP activity in serum and levels of collagen fragments (NTX) in urine increased for all patients temporarily during the 7 days of treatment with HD-Sim indicating that osteoclasts may have been stimulated rather than inhibited. The other markers of bone metabolism showed no change. None of the patients showed any reduction in free monoclonal light chains or monoclonal proteins in serum during treatment with HD-Sim. In spite of the fact that bone turn over effects of HD-Sim may have been blunted by concomitant treatment of patients with other drugs we observed a transient increase in markers of osteoclast activity. This sign of a transient stimulation of osteoclast activity suggests that HD-Sim may be harmful rather than beneficial for MM patients. For this reason and because of gastro-intestinal side effects the study was stopped prematurely.

Enhanced Hype

The recently published Effect of Combination Ezetimibe and High-Dose Simvastatin vs. Simvastatin Alone on the Atherosclerotic Process in Patients With Heterozygous Familial Hypercholesterolemia (ENHANCE) trial seems to raise questions regarding the notion that lipid lowering is of benefit in the prevention and treatment of vascular disease. Before one can make this conclusion, a careful analysis of the trial, including the subjects included and the surrogate end point studied, is required. The results of this study should be taken in context with those of many other studies showing that lipid lowering by many approaches is beneficial. In conclusion, the public fury over this study, with physicians making unsupported statements to the press and on the Web, is unfortunate and should be discouraged in the future.

Effect of statins in 'upstream therapy' of atrial fibrillation: better reliability with implantable cardiac monitors

The therapeutic potential to suppress atrial fibrillation (AF) is currently under evaluation for several non-antiarrhythmic drugs: angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers, aldosterone receptor antagonists, anti-inflammatory and antioxidative drugs, polyunsaturated fatty acids, and HMG-CoA reductase inhibitors, i.e. statins. Statins have shown multiple (‘pleiotropic’) beneficial effects beyond lowering of cholesterol: anti-inflammatory, antioxidant, and antifibrotic effects, modulation of matrix metalloproteinases, interaction with peroxisome receptors that regulate proliferation, and with endothelial nitric oxide synthase, protecting atrial myocardium during ischaemia.1 For these reasons, statins may be able to decelerate or even reverse structural remodelling in patients with AF. Additionally, pre-treatment with high-dose atorvastatin prevented electrical remodelling in a pericarditis dog model,2 and high-dose simvastatin attenuated downregulation of calcium channel subunits, preventing shortening of atrial refractoriness, a central element of electrical remodelling in AF.3 However, this sounds familiar: positive effects on intracellular calcium handling and atrial electrical remodelling have also been reported in animal studies with verapamil,4,5 but this drug disappointed in clinical trials, being unable to prevent atrial electrical remodelling and recurrence of AF.6,7 For statins and AF suppression, there are not only in vitro and animal studies available but also results from 16 clinical trials.1 Nine of … *Corresponding author. Tel: +49 69 6301 7387, Fax: +49 69 6301 3813, Email: C.W.Israel{at}em.uni-frankfurt.de

The Pleiotropic Effects of Simvastatin on Retinal Microvascular Endothelium Has Important Implications for Ischaemic Retinopathies

BackgroundCurrent guidelines encourage the use of statins to reduce the risk of cardiovascular disease in diabetic patients; however the impact of these drugs on diabetic retinopathy is not well defined. Moreover, pleiotropic effects of statins on the highly specialised retinal microvascular endothelium remain largely unknown. The objective of this study was to investigate the effects of clinically relevant concentrations of simvastatin on retinal endothelium in vitro and in vivo.Methods and FindingsRetinal microvascular endothelial cells (RMECs) were treated with 0.01–10 µM simvastatin and a biphasic dose-related response was observed. Low concentrations enhanced microvascular repair with 0.1 µM simvastatin significantly increasing proliferation (p<0.05), and 0.01 µM simvastatin significantly promoting migration (p<0.05), sprouting (p<0.001), and tubulogenesis (p<0.001). High concentration of simvastatin (10 µM) had the opposite effect, significantly inhibiting proliferation (p<0.01), migration (p<0.01), sprouting (p<0.001), and tubulogenesis (p<0.05). Furthermore, simvastatin concentrations higher than 1 µM induced cell death. The mouse model of oxygen-induced retinopathy was used to investigate the possible effects of simvastatin treatment on ischaemic retinopathy. Low dose simvastatin(0.2 mg/Kg) promoted retinal microvascular repair in response to ischaemia by promoting intra-retinal re-vascularisation (p<0.01). By contrast, high dose simvastatin(20 mg/Kg) significantly prevented re-vascularisation (p<0.01) and concomitantly increased pathological neovascularisation (p<0.01). We also demonstrated that the pro-vascular repair mechanism of simvastatin involves VEGF stimulation, Akt phosphorylation, and nitric oxide production; and the anti-vascular repair mechanism is driven by marked intracellular cholesterol depletion and related disorganisation of key intracellular structures.ConclusionsA beneficial effect of low-dose simvastatin on ischaemic retinopathy is linked to angiogenic repair reducing ischaemia, thereby preventing pathological neovascularisation. High-dose simvastatin may be harmful by inhibiting reparative processes and inducing premature death of retinal microvascular endothelium which increases ischaemia-induced neovascular pathology. Statin dosage should be judiciously monitored in patients who are diabetic or are at risk of developing other forms of proliferative retinopathy.