Simvastatin has anti-inflammatory and antiatherosclerotic activities independent of plasma cholesterol lowering

Inhibitors of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase, such as simvastatin, lower circulating cholesterol levels and prevent myocardial infarction. Several studies have shown an unexpected effect of HMG-CoA reductase inhibitors on inflammation. Here, we confirm that simvastatin is anti-inflammatory by using a classic model of inflammation: carrageenan-induced foot pad edema. Simvastatin administered orally to mice 1 hour before carrageenan injection significantly reduced the extent of edema. Simvastatin was comparable to indomethacin in this model. To determine whether the anti-inflammatory activity of simvastatin might affect atherogenesis, simvastatin was tested in mice deficient in apoE. Mice were dosed daily for 6 weeks with simvastatin (100 mg/kg body wt). Simvastatin did not alter plasma lipids. Atherosclerosis was quantified through the measurement of aortic cholesterol content. Aortas from control mice (n=20) contained 56+/-4 nmol total cholesterol/mg wet wt tissue, 38+/-2 nmol free cholesterol/mg, and 17+/-2 nmol cholesteryl ester/mg. Simvastatin (n=22) significantly (P<0.02) decreased these 3 parameters by 23%, 19%, and 34%, respectively. Histology of the atherosclerotic lesions showed that simvastatin did not dramatically alter lesion morphology. These data support the hypothesis that simvastatin has antiatherosclerotic activity beyond its plasma cholesterol-lowering activity.     

Vascular endothelial growth factor regulation of Weibel-Palade-body exocytosis

Vascular endothelial growth factor (VEGF) not only regulates angiogenesis, vascular permeability, and vasodilation but also promotes vascular inflammation. However, the molecular basis for the proinflammatory effects of VEGF is not understood. We now show that VEGF activates endothelial cell exocytosis of Weibel-Palade bodies, releasing vasoactive substances capable of causing vascular thrombosis and inflammation. VEGF triggers endothelial exocytosis in part through calcium and phospholipase C-gamma (PLC-gamma) signal transduction. However, VEGF also modulates endothelial cell exocytosis by activating endothelial nitric oxide synthase (eNOS) production of nitric oxide (NO), which nitrosylates N-ethylmaleimide sensitive factor (NSF) and inhibits exocytosis. Thus, VEGF plays a dual role in regulating endothelial exocytosis, triggering pathways that both promote and inhibit endothelial exocytosis. Regulation of endothelial exocytosis may explain part of the proinflammatory effects of VEGF.     

Ceramide triggers Weibel-Palade body exocytosis

The sphingolipid ceramide mediates a variety of stress responses, including vascular inflammation and thrombosis. Activated endothelial cells release Weibel-Palade bodies, granules containing von Willebrand factor (vWF) and P-selectin, which induce leukocyte rolling and platelet adhesion and aggregation. We hypothesized that ceramide induces vascular inflammation and thrombosis in part by triggering Weibel-Palade body exocytosis. We added ceramide to human aortic endothelial cells and assayed Weibel-Palade body exocytosis by measuring the concentration of vWF released into the media. Exogenous ceramide induces vWF release from endothelial cells in a dose-dependent manner. Activators of endogenous ceramide production, neutral sphingomyelinase, or tumor necrosis factor-alpha also induce Weibel-Palade body exocytosis. We next studied NO effects on ceramide-induced Weibel-Palade body exocytosis because NO can inhibit vascular inflammation. The NO donor S-nitroso-N-acetylpenicillamine decreases ceramide-induced vWF release in a dose-dependent manner, whereas the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester increases ceramide-induced vWF release. In summary, our findings show that endogenous ceramide triggers Weibel-Palade body exocytosis, and that endogenous NO inhibits ceramide-induced exocytosis. These data suggest a novel mechanism by which ceramide induces vascular inflammation and thrombosis.     

Sphingosine 1-phosphate activates Weibel-Palade body exocytosis

Sphingosine 1-phosphate (S1P) not only regulates angiogenesis, vascular permeability and vascular tone, but it also promotes vascular inflammation. However, the molecular basis for the proinflammatory effects of S1P is not understood. We now show that S1P activates endothelial cell exocytosis of Weibel-Palade bodies, releasing vasoactive substances capable of causing vascular thrombosis and inflammation. S1P triggers endothelial exocytosis in part through phospholipase C-gamma signal transduction. However, S1P also modulates endothelial cell exocytosis by activating endothelial nitric oxide synthase production of nitric oxide, which inhibits exocytosis. Thus S1P plays a dual role in regulating endothelial exocytosis, triggering pathways that both promote and inhibit endothelial exocytosis. Regulation of endothelial exocytosis may explain part of the proinflammatory effects of S1P.     

3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors interfere with angiogenesis by inhibiting the geranylgeranylation of RhoA

Angiogenesis is implicated in the pathogenesis of cancer, rheumatoid arthritis, and atherosclerosis and in the treatment of coronary artery and peripheral vascular disease. Here, cholesterol-lowering agents, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, are shown to interfere with angiogenesis. In vivo, the HMG-CoA reductase inhibitor simvastatin dose-dependently inhibited capillary growth in both vascular endothelial growth factor-stimulated chick chorioallantoic membranes and basic fibroblast growth factor-stimulated mouse corneas. In vitro, the development of tubelike structures by human microvascular endothelial cells cultured on 3D collagen gels was inhibited at simvastatin concentrations similar to those found in the serum of patients on therapeutic doses of this agent. HMG-CoA reductase inhibitors interfered with angiogenesis via inhibition of the geranylgeranylation and membrane localization of RhoA. Simvastatin inhibited membrane localization of RhoA with a concentration dependence similar to that for the inhibition of tube formation, whereas geranylgeranyl pyrophosphate, the substrate for the geranylgeranylation of Rho, reversed the effect of simvastatin on tube formation and on the membrane localization of RhoA. Furthermore, tube formation was inhibited by GGTI, a specific inhibitor of the geranylgeranylation of Rho; by C3 exotoxin, which inactivates Rho; and by the adenoviral expression of a dominant-negative RhoA mutant. The expression of a dominant-activating RhoA mutant reversed the effect of simvastatin on tube formation. Finally, HMG-CoA reductase inhibitors inhibited signaling by vascular endothelial growth factor, Akt, and focal adhesion kinase, three RhoA-dependent pathways known to be involved in angiogenesis. This study demonstrates a new relationship between lipid metabolism and angiogenesis and an antiangiogenic effect of HMG-CoA reductase inhibitors with possible important therapeutic implications.     

Direct vascular and cardioprotective effects of rosuvastatin,a new HMG-CoA reductase inhibitor

OBJECTIVE: We examined the possible effects of a novel 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, rosuvastatin, on endothelial nitric oxide (NO) production and myocardial ischemia-reperfusion injury. BACKGROUND: Recent studies suggest that HMG-CoA reductase inhibitors promote vascular endothelial function through enhanced endothelial NO production. However, it is unclear whether all statins share this beneficial side effect or whether this effect is limited to the "natural" statins. METHODS: Wild-type mice (n = 158) were subjected to 30 min of regional myocardial ischemia and 24 h of reperfusion. Mice were treated with various doses of rosuvastatin (0.1, 0.5, 1.0, 2.0, and 5.0 mg/kg) 18 h before myocardial ischemia and reperfusion.RESULTS: Rosuvastatin significantly increased NO production from the vascular endothelium following acute administration to mice. In addition, rosuvastatin increased myocardial endothelial nitric oxide synthase (eNOS) messenger ribonucleic acid levels. Myocardial necrosis was reduced by approximately 40% with rosuvastatin therapy. Rosuvastatin attenuated myocardial injury when it was administered 6 h, but not 0 h or 3 h, before myocardial ischemia. In additional studies, rosuvastatin did not affect myocardial infarct size in eNOS-deficient mice compared to vehicle-treated eNOS mice. CONCLUSION: These data demonstrate that rosuvastatin increases vascular endothelial NO production and attenuates myocardial necrosis following ischemia and reperfusion in mice.     

Simvastatin inhibits leukocyte-endothelial cell interactions and protects against inflammatory processes in normocholesterolemic rats

Simvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has been shown to lower serum cholesterol levels and normalize endothelial cell function. Moreover, HMG-CoA reductase inhibitors exert beneficial effects in coronary artery and cerebrovascular diseases. We examined the effects of simvastatin on leukocyte-endothelial cell interaction in vivo by intravital microscopy. Simvastatin (12.5 or 25 microg per rat) was given 18 hours before study. Superfusion with the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 50 micromol/L) significantly increased leukocyte rolling from 12+/-2 to 60+/-8 leukocytes per minute, increased adherence to the mesenteric endothelium from 1.8+/-0.5 to 17+/-1.2 leukocytes per 100 microm of venular length, and raised leukocyte transmigration from 2.5+/-1.0 to 10+/-2 leukocytes per perivessel area (P<0.01). Similar results were obtained with thrombin (0.5 U/mL) superfusion of the mesentery. In contrast, pretreatment with simvastatin (25 microg per rat IP) significantly attenuated L-NAME-stimulated leukocyte rolling, to 12+/-2 (P<0.01); adherence, to 5+/-0.5 leukocytes per 100 microm (P<0.01); and leukocyte transmigration, to 3.5+/-1.5 leukocytes per perivessel area (P<0.01). Similar results were obtained in thrombin-superfused mesenteries. Moreover, immunohistochemical analysis demonstrated significantly increased P-selectin expression on the mesenteric venular endothelium after superfusion with either L-NAME (P<0.01) or thrombin (P<0.01), which was significantly attenuated by simvastatin. These results clearly demonstrate that simvastatin is a potent and effective endothelium-protective agent that reduces leukocyte-endothelial cell interactions independently of its well-known lipid-lowering effects. This effect was found to be at least partially mediated via downregulation of P-selectin expression on the microvascular endothelium. Thus, HMG-CoA reductase inhibitors like simvastatin have important anti-inflammatory effects besides their well-known lipid-lowering action.     

Simvastatin in primary biliary cirrhosis: effects on serum lipids and distinct disease markers

BACKGROUND/AIMS: Primary biliary cirrhosis (PBC) is an autoimmune disease of the liver with inflammation of small and middle-sized bile ducts. Serum lipids are frequently elevated, but the use of a lipid lowering drug therapy in PBC is still a matter of debate. Application of an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in hypercholesterolemic PBC patients was therefore the subject of the present study. METHODS: Six female patients (aged 46.5 (32-61) years; median (range)) were treated with the HMG-CoA reductase inhibitor simvastatin (5 or 20 mg/day). Levels of serum total cholesterol, low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol were determined prior to and after 2 months of treatment. Concentrations of serum markers of cholestasis, antimitochondrial antibodies (AMA), and immunoglobulins A, G and M were also assessed. RESULTS: Simvastatin significantly (P<0.05) reduced serum levels of total cholesterol, LDL cholesterol, alkaline phosphatase, -glutamyltransferase, and immunoglobulin M (by 19, 26, 12, 37 and 14%, respectively). CONCLUSIONS: The lipid lowering potency of the HMG-CoA reductase inhibitor simvastatin was confirmed in hypercholesterolemic patients with PBC. The drug might also prove useful as modulator of cholestasis and of immune response in this disease.     

Regulation of Weibel-Palade body exocytosis

Weibel-Palade bodies (WPBs) are endothelial granules that store von Willebrand factor (VWF), P-selectin, and other vascular modulators. Endothelial cells secrete WPBs in response to vascular injury, releasing VWF, which triggers platelet rolling, and externalizing P-selectin, which activates leukocyte trafficking. Endothelial exocytosis is one of the earliest responses to vascular damage and plays a pivotal role in thrombosis and inflammation. This review examines the regulation of WPB exocytosis-the exocytic machinery, activators, and inhibitors of exocytosis-and speculates about the development of novel anti-exocytic drugs.     

Simvastatin reduces human atrial myofibroblast proliferation independently of cholesterol lowering via inhibition of RhoA

OBJECTIVE: Adverse atrial and ventricular myocardial remodeling is characterized by fibrosis, myocyte death or hypertrophy and fibroblast proliferation. HMG-CoA reductase inhibitors (statins) are widely prescribed cholesterol-lowering drugs that also appear to have beneficial effects on myocardial remodeling. Although statins are known to reduce myocyte hypertrophy, their effect on cardiac fibroblast proliferation is unknown. The purpose of this study was to investigate the effects of simvastatin on human atrial myofibroblast proliferation. METHODS: Cardiac myofibroblasts were cultured from biopsies of human right atrial appendage. Proliferation was quantified by cell counting and cell cycle progression determined by immunoblotting for Cyclin A. The expression, activation and intracellular localization of RhoA were investigated using immunoblotting and immunocytochemistry. RESULTS: Simvastatin (0.1-1.0 micromol/l) inhibited serum-induced myofibroblast proliferation in a concentration-dependent manner at a point upstream of Cyclin A expression. These effects were reversed by mevalonate or geranylgeranyl pyrophosphate (GGPP), but not squalene or farnesyl pyrophosphate (FPP), indicating a mechanism involving inhibition of Rho-family GTPases and independent of cholesterol synthesis. The effects of simvastatin were mimicked by inhibiting Rho geranylgeranylation or Rho-kinase activation. Furthermore, we demonstrated that simvastatin inhibited RhoA function by preventing its association with the plasma membrane and hence, its interaction with downstream effectors required for cell proliferation. CONCLUSIONS: Simvastatin reduced proliferation of cultured human atrial myofibroblasts independently of cholesterol synthesis via a mechanism involving inhibition of RhoA geranylgeranylation. Statins may therefore have an important role in preventing adverse myocardial remodeling associated with cardiac myofibroblast proliferation.     

A head-to-head comparison of the cost effectiveness of HMG-CoA reductase inhibitors and fibrates in different types of primary hyperlipidemia

Summary The objective of this study was to compare the lifetime cost-effectiveness of HMG-CoA reductase inhibitors and fibrates for the treatment of hyperlipidemia. Estimates of lipid modification achieved due to drug therapy were based on published head-to-head comparisons of specific HMG-CoA reductase inhibitors and fibrates in randomized, double-blind studies. We used a validated coronary heart disease (CHD) prevention computer model to estimate the costs and benefits of lifelong lipid modification. The patients were middle-aged men and women who were free of CHD, with either primary type IIa or IIb hyperlipidemia. The intervention used were specific HMG-CoA reductase inhibitors and fibrates at several dosages, which reduced total cholesterol 11–34% and increased high-density lipoprotein cholesterol 1–29%. The main outcome measure was the cost per year of life saved after discounting benefits and costs by 5% annually. The lifetime cost effectiveness of HMG-CoA reductase inhibitors (fluvastatin, lovastatin, pravastatin, simvastatin) and fibrates (bezafibrate, fenofibrate, gemfibrozil) for the treatment of primary hyperlipidemia varied according to patient population, the effectiveness of each drug in modifying lipid levels, and the price of each drug. The estimates of cost per year of life saved for HMG-CoA reductase inhibitors range from $19,886 to $73,632, and $16,955 to $59,488 for fibrates according to gender and type of primary hyperlipidemia. Fluvastatin 20 mg/day was significantly more cost effective than gemfibrozil 1200 mg/day for male patients with type IIa hyperlipidemia. Simvastatin 17.3 mg/day or 20 mg/day yielded similar cost-effectiveness ratios compared with fibrates among type II hyperlipidemic patients. However, micronized fenofibrate was more cost effective than simvastatin 20 mg/day among type IIb patients. The cost effectiveness of lipid therapy varies widely and can be maximized by selecting specific drugs for specific lipid abnormalities.     

Effect of long-term cholesterol-lowering treatment with HMG-CoA reductase inhibitor (simvastatin) on myocardial perfusion evaluated by thallium-201 single photon emission computed tomography

Fifteen patients with either angina pectoris or old myocardial infarction, who had positive 201Tl single photon emission computed tomography (SPECT) imaging and coronary sclerosis of more than 50%, were treated with an HMG-CoA reductase inhibitor (simvastatin) for more than 1 year. They were compared with an untreated control group (n = 25). Total cholesterol decreased 22% and high-density lipoprotein (HDL) increased 9% with simvastatin; both changes were significantly different from those in controls. Long-term simvastatin induced improvement of myocardial perfusion on 201Tl SPECT images both during exercise and at rest, which was also significantly different from controls. In addition, the improvement of myocardial perfusion on 201Tl SPECT images was clearly related to the improvements in cholesterol values, especially nonHDL cholesterol. Thus, the greater the decrease in nonHDL cholesterol, the greater the improvement in myocardial perfusion at rest or during exercise with long-term treatment using an HMG-CoA reductase inhibitor. These findings indicate that the improvements in cholesterol values caused by HMG-CoA reductase inhibitor therapy are related to improvements of myocardial perfusion seen on 201Tl SPECT images.     

Small GTP-binding protein Ral modulates regulated exocytosis of von Willebrand factor by endothelial cells

Weibel-Palade bodies are endothelial cell-specific organelles, which contain von Willebrand factor (vWF), P-selectin, and several other proteins. Recently, we found that the small GTP-binding protein Ral is present in a subcellular fraction containing Weibel-Palade bodies. In the present study, we investigated whether Ral is involved in the regulated exocytosis of Weibel-Palade bodies. Activation of endothelial cells by thrombin resulted in transient cycling of Ral from its inactive GDP-bound to its active GTP-bound state, which coincided with release of vWF. Ral activation and exocytosis of Weibel-Palade bodies were inhibited by incubation with trifluoperazine, an inhibitor of calmodulin, before thrombin stimulation. Functional involvement of Ral in exocytosis was further investigated by the expression of constitutively active and dominant-negative Ral variants in primary endothelial cells. Introduction of active Ral G23V resulted in the disappearance of Weibel-Palade bodies from endothelial cells. In contrast, the expression of the dominant-negative Ral S28N did not affect the amount of Weibel-Palade bodies in transfected cells. These results indicate that Ral is involved in regulated exocytosis of Weibel-Palade bodies by endothelial cells.     

Simvastatin enhances myocardial angiogenesis induced by vascular endothelial growth factor gene transfer

Statins have cardioprotective roles. We explored the cardiac angiogenic effects of simvastatin in combination with transient overexpression of vascular endothelial growth factor (VEGF). Compared with normal mice, 1-year-old ApoE(-/-) mice fed on a high-fat diet (HFD) had about 30% less myocardial capillary (P < 0.001) and arteriolar (P < 0.03) densities, associated with decreased VEGF (55%), VEGFR-1 (56%) and VEGFR-2 (78%) mRNA expressions and myocardial endothelial nitric oxide synthase (eNOS) production (58%). By contrast, angiopoietin-1 and angiopoietin-2 mRNA expressions were increased (500% P < 0.02, and 400% P < 0.01, respectively) in the ApoE(-/-) hearts. No change was observed in Tie-2 gene expression. Phosphorylation of antiapoptotic Akt was lower and proapoptotic p38 mitogen-activated protein kinase (MAPK) was higher in the ApoE(-/-) mice compared with controls. Intramyocardial VEGF gene transfer increased capillary and arteriolar densities in the ApoE(-/-) mice, and simvastatin treatment further enhanced capillary density (P < 0.03) to a level similar to that of normal mice. Simvastatin did not change the lipid profile but blocked p38 MAPK phosphorylation in the ApoE(-/-) myocardium. Concurrent with these changes, there were increased levels of expression of mVEGF (P < 0.04) and VEGFR-2 (P < 0.03) mRNAs and increased production of eNOS (P < 0.05) in the ApoE(-/-) mice, while no changes were detected in the angiopoietin system. Thus, increased myocardial angiogenesis in the ApoE(-/-) mice following transient overexpression of VEGF is further increased by additional simvastatin treatment. These effects occurred concurrently with simvastatin-induced stimulation of the VEGF system, increased eNOS production and reduction in p38 MAPK phosphorylation.     

Simvastatin-induced rhabdomyolysis and acute renal injury

Simvastatin is one of the most commonly prescribed CoA reductase inhibitors. The safety profile of this drug has been widely discussed in the medical and consumer advocacy communities. Like other statins, simvastatin can cause a serious and potentially life-threatening complication: rhabdomyolysis. We describe a case of simvastatin-induced rhabdomyolysis complicated by acute renal failure requiring urgent hemodialysis. The relative safety of simvastatin compared to other HMG-CoA reductase inhibitors and the conditions that can potentiate its toxicity are discussed. The clinical features of rhabdomyolysis, and subsequent acute renal failure, and their treatment modalities are presented.     

Simvastatin and cholestyramine in the long-term treatment of hypercholesterolaemia

After 6 weeks on a lipid-lowering diet, 20 outpatients with type II hyperlipoproteinaemia (18 type IIa) were randomized to treatment with cholestyramine 12 g b.i.d. (5 patients) or simvastatin (a new HMG-CoA reductase inhibitor) 40 mg q.p.m. (15 patients) for 12 weeks. From week 13 to week 20 nine patients in the simvastatin group and all patients in the cholestyramine group were treated with the combination of the two drugs. From week 21 to week 52 all patients were on monotherapy with simvastatin. Simvastatin treatment reduced low-density lipoprotein (LDL) cholesterol by 40% after 12 weeks, compared with 33% in the cholestyramine group. This difference was not significant. The total reductions of LDL-cholesterol on combination therapy were respectively 60% and 56% in each group. After 52 weeks LDL-cholesterol was still reduced by 36% (P less than 0.001) on monotherapy with simvastatin. Simvastatin also reduced triglycerides (TG) by 17% (P less than 0.05) and high-density lipoprotein (HDL) cholesterol was increased by 19% (P less than 0.01). No serious side effects were observed, and the new HMG-CoA reductase inhibitors may offer a new approach to the treatment of hypercholesterolaemia.     

Interaction between amlodipine and simvastatin in patients with hypercholesterolemia and hypertension.

3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors are often prescribed in association with antihypertensive agents, including calcium antagonists. Simvastatin is an HMG-CoA reductase inhibitor that is metabolized by the cytochrome P450 (CYP) 3A4. The calcium antagonist amlodipine is also metabolized by CYP3A4. The purpose of this study was to investigate drug interactions between amlodipine and simvastatin. Eight patients with hypercholesterolemia and hypertension were enrolled. They were given 4 weeks of oral simvastatin (5 mg/day), followed by 4 weeks of oral amlodipine (5 mg/day) co-administered with simvastatin (5 mg/day). Combined treatment with simvastatin and amlodipine increased the peak concentration (C(max)) of HMG-CoA reductase inhibitors from 9.6 +/- 3.7 ng/ml to 13.7 +/- 4.7 ng/ml (p < 0.05) and the area under the concentration-time curve (AUC) from 34.3 +/- 16.5 ng h/ml to 43.9 +/- 16.6 ng h/ml (p < 0.05) without affecting the cholesterol-lowering effect of simvastatin. This study is the first to determine prospectively the pharmacokinetic and pharmacodynamic interaction between amlodipine and simvastatin.     

Nitric oxide synthase II (NOS II) gene expression correlates with atherosclerotic intimal thickening. Preventive effects of HMG-CoA reductase inhibitors.

HMG-CoA reductase inhibitors have been shown to be effective in primary and secondary prevention of coronary heart disease. Their mechanism of action is attributed to their cholesterol lowering activity but recent results seem to indicate additional effects related to the modulation of other processes that regulate the presentation of vascular diseases. Our objective has been to study the effects of atorvastatin and simvastatin, two HMG-CoA reductase inhibitors, on lesion composition and expression of genes involved in lesion development in a diet-induced atherosclerotic rabbit model. Both HMG-CoA reductase inhibitors were administered at identical doses of 2.5 mg/kg per day with the hyperlipemic diet for 10 weeks. Both statins significantly prevented the diet-induced increase in cholesterol levels. Relative lesion composition in fibrinogen, macrophages and smooth muscle cells was unaltered by the treatment although lesion size was reduced; therefore, both HMG-CoA reductase inhibitors reduced total amounts of fibrinogen, macrophages and smooth muscle cells (simvastatin, P < 0.05). NOS II gene expression was positively and significantly correlated with lesion size and inversely correlated with HDL plasma levels. NOS II expression was markedly downregulated in simvastatin treated animals while MCP-1 was unaltered. Therefore, HMG-CoA reductase inhibition seems to interfere with atherosclerotic lesion development by reducing intimal thickening development and the expression of the cytotoxic NOS II.     

Simvastatin, a competitive inhibitor of HMG-CoA reductase, lowers cholesterol saturation index of gallbladder bile

We tested the possibility that simvastatin, a competitive inhibitor of HMG-CoA reductase related to mevinolin, might alter cholesterol saturation of gallbladder bile. Ten patients with Type IIa or IIb hypercholesterolemia underwent bile sampling before, and again after, treatment with 20 or 40 mg per day simvastatin for 7 to 13 weeks. Mean cholesterol saturation index of gallbladder bile fell from 1.01 to 0.77 during simvastatin treatment (p less than 0.01). This finding strongly suggests that treatment with HMG-CoA reductase inhibitors will not predispose to development of cholesterol gallstones. Indeed, it raises the possibility that such inhibitors might have a future role to play in treatment of gallstones.