Objective-Pleiotropic atheroprotective effects of HMG-CoA reductase inhibitors may be mediated on the level of vascular gene transcription. The aim of this study was to characterize the effects of statins on the activation of transcription factors known to regulate inflammation and cell proliferation/differentiation. Methods and Results-Simvastatin, atorvastatin, and lovastatin (0.1 to 10 mol/L) inhibited the binding of nuclear proteins to both the nuclear factor-kappa B (NF-B) and activator protein-1 (AP-1) DNA consensus oligonucleotides in human endothelial and vascular smooth muscle cells as assessed by electrophoretic mobility shift assay ( Key Words: statins Ⅲ nuclear factor-B Ⅲ activator protein-1 Ⅲ hypoxia-inducible factor-1␣ Ⅲ vascular endothelial growth factor R andomized clinical trials have clearly shown the benefit of statin therapy in the reduction of cardiovascular events and total mortality in coronary heart disease patients with either high or normal cholesterol levels. 1 In these studies, survival curves began to diverge within a relatively short period of time and before effects on plaque size were likely to occur. Demonstrated effects of HMG-CoA reductase inhibitors were not reflected by a regression in coronary stenoses as assessed by angiography. These findings have suggested that mechanisms of statins beyond lipid lowering are likely to be involved in the reduction of coronary events. 2 Both in vivo and in vitro studies support the notion that statins counteract the chronic subclinical vascular inflammatory state associated with atherosclerosis. 3,4 Statins inhibit leukocyte-endothelium interaction 5-7 and decrease inflammation in carotid lesions in humans. 8 Many of the vasculoprotective effects of HMG-CoA reductase inhibitors seem to be mediated by enhanced availability of nitric oxide. 9 There is increasing evidence that statins may act on the transcriptional level as well, eg, simvastatin inhibited endothelial secretion of PAI-1, which was correlated with reduced mRNA transcription and activity of the promoter. 10 Despite extensive research on molecular mechanisms of statins, little is known about the interactions of these drugs with transcription factors. The aim of this study was to characterize the effects of simvastatin, atorvastatin, and lovastatin on the activation of nuclear factor (NF)-B, activator protein (AP)-1, and hypoxia-inducible factor (HIF)-1␣ in endothelial and arterial smooth muscle cells. Because these factors regulate the transcription of many genes, including cytokines, chemokines, adhesion molecules, and growth factors, such interactions of statins on vascular cell signaling and gene expression may explain atheroprotective effects not directly related to cholesterol lowering. MethodsSimvastatin (MSD) and lovastatin (Calbiochem) prodrugs were activated from their inactive lactone proforms to their active dihy-

Objective-Atherosclerosis is associated with an immune response against oxidized LDL, which modulates the progression of the disease process. Methods and Results-Using a library of polypeptides covering the complete sequence of apoB-100, the only major protein of LDL, we have identified over 100 different human antibodies reacting against aldehyde-modified apoB-100 sequences. IgM antibody titer levels decreased with age and were associated with the intima-media thickness of the carotid artery in subjects younger than 60 years. There were also inverse associations between IgM levels and oxidized LDL in plasma. In prospective clinical studies, antibody levels against several aldehyde-modified apoB-100 sites were associated with cardiovascular disease in this age group. Whether this immune response is adaptive (protective) or maladaptive (causal) in atherosclerosis requires further investigation. Conclusions-We have characterized a large number of epitopes within the apoB-100 component of oxidized LDL that provoke an immune response in humans. These findings will make it possible to study the role of immune responses against specific sites in oxidized LDL and to determine whether these immune responses influence the risk for future cardiac events.

Background-Accumulation and oxidation of LDL are believed to be important initiating factors in atherosclerosis.Oxidized LDL is recognized by the immune system, and animal studies have suggested that these immune responses have a protective effect against atherosclerosis. Aldehyde-modified peptide sequences in apolipoprotein B-100 (apoB-100) are major targets for these immune responses. Methods and Results-Human IgG1 antibodies against 2 malondialdehyde (MDA)-modified apoB-100 peptide sequences were produced through screening of a single-chain antibody-fragment library and subsequent cloning into a pcDNA3 vector. Three weekly doses of these antibodies were injected into male apoE Ϫ/Ϫ mice. Phosphate-buffered saline and human IgG1 antibodies against fluorescein isothiocyanate were used as controls. One of the IgG1 antibodies significantly and dose-dependently reduced the extent of atherosclerosis as well as the plaque content of oxidized LDL epitopes and macrophages. In cell culture studies, human monocytes were incubated with native LDL or oxidized LDL, in the presence of antibodies. The same antibody induced an increase in monocyte binding and uptake of oxidized LDL. Conclusions-These findings suggest that antibodies are important mediators of atheroprotective immune responses directed to oxidized LDL. Thus, passive immunization against MDA-modified apoB-100 peptide sequences may represent a novel therapeutic approach for prevention and treatment of cardiovascular disease.