Inhibitors of HMG-CoA reductase sensitize human smooth muscle cells to Fas-ligand and cytokine-induced cell death

Lupus-Like Syndrome Associated with Statin Therapy

Statins are among the most widely prescribed drugs. An increasing number of lupus-like syndrome has recently been reported with these lipid-lowering agents. We describe a new case associated with simvastatin therapy. The presence of anti-dsDNA antibodies in the serum is for the first time reported confirming that statins may also induce a systemic autoimmune reaction. Statin-induced lupus-like syndrome is characterized by the long delay between the beginning of therapy and the skin eruption. Antinuclear antibodies may persist for many months after drug discontinuation. The causal relationship may be therefore difficult to establish, and probably many cases are unrecognized. Early diagnosis may avoid unnecessary immunosuppressive therapy.

NO and angiogenesis

Angiogenesis requires the elaboration of endothelium-derived nitric oxide (NO). Angiogenic factors induce the release of NO from endothelial cells, which mediates a multiplicity of processes involved in angiogenesis. These NO-modulated processes include endothelial cell survival, proliferation, migration, and interaction with the extracellular matrix. Derangements of the NO synthase pathway impair angiogenesis. Accordingly, the competitive inhibitor of the NOS pathway asymmetric dimethylarginine (ADMA) acts as an endogenous inhibitor of angiogenesis. By contrast, agents which increase NO synthesis, such as low dose statins, enhance angiogenesis. Modulation of the NO synthase pathway could become a new therapeutic avenue for angiogenesis-related disorders.

Polymyosites induites ou associées aux traitements hypolipémiants ?

PURPOSE

Rhabdomyolysis and myositis are rare, dose-related complications of statins and fenofibrates. The outcome is favorable as a rule with rapid regression after stopping the responsible drug. Recently, various auto-immune disease with evidence of hypersensitivity to HMG-CoA reductase inhibitors or fibrates drugs have been reported. Less than ten cases of dermatomyositis and polymyositis due to cholesterol-lowering drugs (CLD) have been previously reported. Five more cases polymyositis associated with CLD are reported.

METHODS

Symptoms were compatible with diagnosis of polymyositis according to Bohan and Peter and with previous reported criteria for drug-induced myopathy in all cases. None of these patients had previous other connective tissue disorders.

RESULTS

Five patients (median age 68 [54-78], female N =4) with CLD treatment (statin N =4, fenofibrates N =1) have developed iatrogenic polymyositis. All of them presented both proximal muscular weakness and increased muscle enzyme levels. One patient had iatrogenic antisynthetase syndrome characterized by mechanic's hand, Raynaud's phenomenon and anti JO1 antibodies. One other had sclerodermic hand oedema. Antinuclear antibodies were positive in 4 cases and muscle biopsy revealed polymyositis infiltrate in 4 cases. CLD treatment was discontinued with partial clinical improvement in 3 cases. Clinical remission was obtained with corticosteroid (N =5) in association with immunosuppresive agents in 3 cases.

CONCLUSION

Muscular symptoms in patient with CLD treatment could be the first symptom of a polymyositis revealed or increased by this treatment and must encourage physician with antinuclear antibodies screening especially in case of proximal muscular weakness and increased muscle enzyme levels.

The Novel HMG-CoA Reductase Inhibitor, Pitavastatin, Induces a Protective Action in Vascular Endothelial Cells through the Production of Nitric Oxide (NO)

This study sought to induce the effect of nitric oxide (NO) production in vascular endothelial cells by Pitavastatin, which is a novel HMG-CoA reductase inhibitor (statin). The growth capacity of vascular endothelial cells significantly (p < 0.01) declined when stimulated with TNF-alpha (10 ng/ml). The growth capacity of the TNF-alpha treated cells recovered, when the TNF-alpha stimulation was performed after Pitavastatin (100 nM) pretreatment. The recovery of the growth capacity of the cells was suppressed by the presence of the NO synthase inhibitor, L-NAME. Pitavastatin increased NO production by the vascular endothelial cells in a dose and time dependent manner. The NO production was suppressed by the presence of mevalonic acid and geranylgeranyl pyrophosphate. In addition, the expression of endothelial nitric oxide synthase was strongly induced by Pitavastatin, and was suppressed by mevalonic acid and geranylgeranyl pyrophosphate by Western blot analysis. Our results show that Pitavastatin induces NO production by vascular endothelial cells, and protects vascular endothelial cells from injury due to the inflammatory reaction induced by TNF-alpha.

Effects of simvastatin administration in an experimental model of cancer cachexia

OBJECTIVE

We evaluated whether statins, in view of their anti-inflammatory properties, may effectively prevent the onset or modulate the severity of muscle wasting during cancer cachexia.

METHODS

Simvastatin was administered to rats bearing the Yoshida AH-130 ascites hepatoma, a well-studied cytokine-dependent experimental model of cancer cachexia.

RESULTS

Quite surprisingly, the drug negatively affected the wasting pattern induced by the AH-130 hepatoma. In fact, the administration of simvastatin to tumor hosts induced a further weight reduction of all the tissues examined except for the soleus, in the absence of significant effects of simvastatin on tumor growth or on food intake. No effects were observed after simvastatin administration in control animals, with the exception of a significant (P < 0.05) reduction in heart weight.

CONCLUSIONS

Simvastatin administration, although capable of negatively modulating the inflammatory response, did not prevent muscle wasting in this experimental model of cancer cachexia. Moreover, the further muscle loss observed in simvastatin-treated tumor-bearing animals suggests that a note of caution should be introduced in treating cancer patients with statins in view of the possible occurrence of harmful side effects.

Statins stimulate arachidonic acid release and prostaglandin I2 production in rat liver cells

Statins inhibit 3-hydroxy-3-methylglutaryl (HMG-CoA) reductase, the rate limiting step in cholesterol synthesis. They are, therefore, used clinically to lower cholesterol and prevent atherosclerosis. Statins have beneficial effects on multiple organ systems. Some of these effects are found in the absence of significant changes in cholesterol levels. Polyunsaturated fatty acids also inhibit HMG-CoA reductase and have many of the same beneficial effects of statins. Four statins (mevastatin, lovastatin, simvastatin and atorvastatin) have been tested in rat liver cells for their effect on arachidonic acid (AA) release and prostaglandin I2 production induced in the presence of lactacystin and 12-O-tetradecanoylphorbol-13-acetate. Each statin stimulated release of AA and induced prostaglandin I2 production. Mevalonate, the product of HMG-CoA reductase, did not reduce the stimulation observed in the presence of simvastatin indicating that HMG-CoA reductase activity is not involved. In view of the multiple biologic properties of AA, the AA released as a result of the action of the statins may play a role in some of the pharmacological effects attributed to these drugs.

Cerivastatin and atorvastatin inhibit IL-3-dependent differentiation and IgE-mediated histamine release in human basophils and downmodulate expression of the basophil-activation antigen CD203c/E-NPP3

Recent data suggest that the statins, apart from their lipid-lowering activity, exhibit profound anti-inflammatory effects. Basophils are major proinflammatory effector cells in diverse pathologic reactions. We have examined the in vitro effects of five different statins on primary human basophils, their progenitors, and the basophil cell line KU-812. Preincubation of blood basophils with cerivastatin or atorvastatin (0.1-100 microM) for 24 h reduced their capacity to release histamine on immunoglobulin E (IgE)-dependent stimulation in a dose-dependent manner. These statins also inhibited IgE-dependent up-regulation of the basophil-activation antigen CD203c. Moreover, both statins suppressed interleukin-3-induced differentiation of basophils from their progenitors as well as (3)H-thymidine uptake in KU-812 cells. All inhibitory effects of cerivastatin and atorvastatin were reversed by mevalonic acid (200 microM). The other statins tested (lovastatin, simvastatin, pravastatin) did not show significant inhibitory effects on basophils. Together, these data identify cerivastatin and atorvastatin as novel inhibitors of growth and activation of human basophils.

Fluvastatin induces apoptosis in rat neonatal cardiac myocytes: a possible mechanism of statin-attenuated cardiac hypertrophy

Hydroxymethylglutaryl CoA (HMG-CoA) reductase inhibitors (statins) have been shown to reduce atherosclerotic cardiovascular mortality and morbidity. Recent evidence indicates that statins may also exert direct effects on vascular wall cells (including endothelial cells and smooth muscle cells) independently of their hypocholesterolemic properties. However, little is known about whether statins have direct effects on myocardium. The effect of lipophilic and hydrophilic statins (fluvastatin and pravastatin) on apoptosis and protein synthesis in rat neonatal cardiac myocytes was investigated. The presence of apoptosis was evaluated by morphologic criteria, electrophoresis of DNA fragments, 4",6"-diamidine-2"-phenylindole (DAPI) staining, and TUNEL assay. Protein synthesis was measured by H-leucine incorporation into the cells. Fluvastatin, but not pravastatin, induced apoptosis in cardiac myocytes in a time- and dose-dependent manner. The pro-apoptotic effect of fluvastatin was reversed in the presence of mevalonate or geranylgeranyl-pyrophosphate (GGPP), but not in the presence of squalene. The addition of protein prenylation inhibitor perillic acid and Rho-kinase inhibitor Y27632 significantly increased apoptosis. Fluvastatin decreased RhoA protein in the membrane fraction, whereas there were no significant changes of the RhoA protein in the cytosol fraction. Interleukin-1beta-stimulated H-leucine incorporation was completely inhibited by fluvastatin, but not by pravastatin. The findings suggest that fluvastatin induces apoptosis in cardiac myocytes via protein prenylation and the subsequent inhibition of Rho, and may play a role in the pathogenesis of cardiac hypertrophy and remodeling.

Potent suppression of proliferation of a10 vascular smooth muscle cells by combined treatment with lovastatin and 3-allylfarnesol, an inhibitor of protein farnesyltransferase

Statins, which inhibit 3-hydroxy-3-methylglutaryl-CoA reductase and thus the synthesis of cholesterol, are remarkably effective in the treatment of cardiovascular disease. In addition to their favorable effect on lipid profile, these drugs may also prevent the proliferation of vascular smooth muscle that is characteristic of atherosclerosis. We hypothesize that statins prevent the post-translational prenylation, and thus inhibit the function, of critical small GTPases in vascular smooth muscle cells. We have therefore assayed the effect of lovastatin on both the growth of A10 vascular smooth muscle cells and the status of their Ras and RhoB proteins. We find that < or =1 microM lovastatin potently inhibits the proliferation of A10 cultures, and higher concentrations (> or =3 microM) induce apoptosis. We have also tested the effect of 3-allylfarnesol (3-alFOH), an inhibitor of farnesyl transferase (FTI). The data show that although > or =10 microM 3-alFOH is required for a cytostatic effect, the action of 3 microM 3-alFOH can be greatly potentiated by even nanomolar levels of lovastatin. We also find that lovastatin and 3-alFOH exhibit synergism to cause the up-regulation and relocalization of RhoB from the membrane to cytosolic compartments. This relocalization of RhoB, which is presumed to reflect an inhibition of its prenylation, correlates with the proapoptotic activities of combined 3-alFOH and lovastatin treatment. These data suggest that RhoB may be a valuable pharmacological target in cardiovascular disease, and that combinations of statins and certain FTIs may be of value in treatment of disorders that are characterized by excess cell proliferation.

Simvastatin induces apoptosis of cultured rat cardiomyocytes

Considering the therapeutic effect of statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) and simvastatin in patients with coronary heart disease, our first hypothesis was that simvastatin should inhibit apoptosis (programmed cell death) in angiotensin II-treated cultured myocytes. But after realizing that simvastatin stimulates apoptosis, we changed our hypothesis and began to study its apoptotic effect in primary cultured rat cardiomyocytes. We found that simvastatin induced apoptosis in a dose-dependent manner (0.1 to 3 micromol/L), as evidenced by the appearance of increased DNA fragmentation in agarose gels and characteristic apoptotic patterns in nuclei labeled with Hoechst 33342, as well as increased activity of caspase 3. FACS analysis of simvastatin-treated cardiomyocytes showing annexin V binding and propidium iodide exclusion ruled out the possibility of necrosis. Increased intracellular enzymatic activity of creatine phosphokinase, aldolase, and lactic dehydrogenase, markers for normal cell function, could reflect the hypertrophic effect of simvastatin. The results indicate that simvastatin-induced apoptosis in cultured heart cells is concentration-dependent and additive to the apoptotic effect of angiotensin II.

Pharmacodynamic activity of drugs and ecotoxicology--can the two be connected?

Therapeutic agents, active substances as well as metabolites, have been detected in the environment, notably in the aquatic compartment. Such contamination may induce adverse environmental effects, and the question is, whether respective hazards could be deduced from their pharmacodynamic properties and activities, and whether there could indeed be relevant risks at the (very low) environmental concentrations observed. While it would seem that, in many cases, the concentrations of drugs needed to elicit pharmacodynamic responses will exceed the environmental concentrations by factors in the range of 10(4)-10(6), and while, furthermore, pharmacodynamically-mediated influences by drug residues on eco-organisms are possible only if the pharmacodynamic target (enzyme, receptor) is expressed and functionally active in some way in the respective eco-organism, such considerations should not, however, deflect from the fact that the specificities of drug substances are defined in terms of the human target structures, and that other organisms may exhibit different specificity profiles. Examples of such species specificities are discussed in this paper and lead to the conclusion that, on the one hand, pharmacodynamic effects, classified as secondary and considered irrelevant for the therapeutic activity in humans, might potentially play a major role in other (non-mammalian) eco-organisms, and that, on the other hand, the--"anthropocentrically" defined--primary pharmacodynamic activities of drugs could induce effects in (non-mammalian) eco-organisms totally different from the therapeutic effects. It is further argued that even slight, non-significant influences on single components within regulatory cascades, like cellular division or signal transduction, that would not result in any acutely discernible effect, might ultimately, through sequential propagation or through interaction with additional, unrelated factors, affect a whole population by its negative consequences on fitness: disturbances in hormonal homeostasis ("endocrine disruption"), in immunological status, in signal transduction or gene activation may serve as examples. From these considerations it is concluded that a more "mechanism-based" approach to the experimental investigation of potential environmental hazards through the contamination of, especially, the aquatic compartment by drug residues should therefore yield more meaningful results and insights than the indiscriminate use of a standard battery of ecotoxicology assays.

Statins have biphasic effects on angiogenesis

BACKGROUND

Statins inhibit HMG-CoA reductase to reduce the synthesis of cholesterol and isoprenoids that modulate diverse cell functions. We investigated the effect of the statins cerivastatin and atorvastatin on angiogenesis in vitro and in vivo.

METHODS AND RESULTS

Endothelial cell proliferation, migration, and differentiation were enhanced at low concentrations (0.005 to 0.01 micromol/L) but significantly inhibited at high statin concentrations (0.05 to 1 micromol/L). Antiangiogenic effects at high concentrations were associated with decreased endothelial release of vascular endothelial growth factor and increased endothelial apoptosis and were reversed by geranylgeranyl pyrophosphate. In murine models, inflammation-induced angiogenesis was enhanced with low-dose statin therapy (0.5 mg x kg(-1) x d(-1)) but significantly inhibited with high concentrations of cerivastatin or atorvastatin (2.5 mg x kg(-1) x d(-1)). Despite the fact that high-dose statin treatment was effective at reducing lipid levels in hyperlipidemic apolipoprotein E-deficient mice, it impaired rather than enhanced angiogenesis. Finally, high-dose cerivastatin decreased tumor growth and tumor vascularization in a murine Lewis lung cancer model.

CONCLUSIONS

HMG-CoA reductase inhibition has a biphasic dose-dependent effect on angiogenesis that is lipid independent and associated with alterations in endothelial apoptosis and vascular endothelial growth factor signaling. Statins have proangiogenic effects at low therapeutic concentrations but angiostatic effects at high concentrations that are reversed by geranylgeranyl pyrophosphate. At clinically relevant doses, statins may modulate angiogenesis in humans via effects on geranylated proteins.

Fluvastatin enhances apoptosis in cytokine-stimulated vascular smooth muscle cells

Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) have been shown to attenuate proliferation of vascular smooth muscle cells (VSMCs) by mechanisms independent of lipid reduction. In the current study, we investigated the effect of lipophilic and hydrophilic statins (fluvastatin and pravastatin) on apoptosis in unstimulated or cytokine-stimulated VSMCs. The presence of apoptosis in rat VSMCs was evaluated by electrophoresis of DNA fragments and 4'6'-diamidine-2'-phenylindole staining and quantified by flow cytometry. Fluvastatin but not pravastatin enhanced apoptosis in interleukin-1beta-stimulated VSMCs. The proapoptotic effect of fluvastatin was fully reversed by mevalonate and geranylgeranyl-pyrophosphate, and partially by farnesyl-pyrophosphate, but not by squalene. Inhibition of the extracellular signal-regulated protein kinase (ERK1/2) pathway significantly increased fluvastatin-enhanced apoptosis, whereas inhibition of the p38-mitogen-activated protein kinase (MAPK) pathway significantly prevented this increase. However, fluvastatin showed no effect on the activity of ERK1/2 and p38-MAPK. Furthermore, fluvastatin-induced apoptosis was inhibited by YVAD-FMK (a caspase-1/interleukin-1beta-converting enzyme-like protease inhibitor) and DEVD-FMK (a caspase-3/CPP32 inhibitor), indicating involvement of an important segment in the apoptosis signaling pathway. These findings suggest that fluvastatin enhances apoptosis in cytokine-stimulated VSMCs and that protein prenylation, MAPK (ERK1/2 and p38-MAPK), and caspases are critically involved in the pathways of fluvastatin-enhanced apoptosis.

Modulation of COX-2 expression by statins in human aortic smooth muscle cells. Involvement of geranylgeranylated proteins

Cyclooxygenase (COX)-2 and COX-1 play an important role in prostacyclin production in vessels and participate in maintaining vascular homeostasis. Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, which is crucial in cholesterol biosynthesis. Recently, cholesterol-independent effects of statins have been described. In this study, we evaluated the effect of two inhibitors of HMG CoA reductase, mevastatin and lovastatin, on the production of prostacyclin and the expression of COX in human aortic smooth muscle cells. Treatment of cells with 25 microm mevastatin or lovastatin resulted in the induction of COX-2 and increase in prostacyclin production. Mevalonate, the direct metabolite of HMG CoA reductase, and geranylgeranyl-pyrophosphate reversed this effect. GGTI-286, a selective inhibitor of geranylgeranyltransferases, increased COX-2 expression and prostacyclin formation, thus indicating the involvement of geranylgeranylated proteins in the down-regulation of COX-2. Furthermore, Clostridium difficile toxin B, an inhibitor of the Rho GTP-binding protein family, the Rho selective inhibitor C3 transferase, and Y-27632, a selective inhibitor of the Rho-associated kinases, targets of Rho A, increased COX-2 expression whereas the activator of the Rho GTPase, the cytotoxic necrotizing factor 1, blocked interlukin-1alpha-dependent COX-2 induction. These results demonstrate that statins up-regulate COX-2 expression and subsequent prostacyclin formation in human aortic smooth muscle cells in part through inhibition of Rho.