Clinical significance of pleiotropic effects of statins: Lipid reduction and beyond

Statins significantly reduce cardiovascular-related morbidity and mortality in patients with and without coronary artery disease. The potential of this drug class has yet to be fully explored. Accumulating evidence from basic research and clinical trials indicates that statins have pleiotropic effects that may largely account for the clinical benefits observed. Potential beneficial effects of these agents include enhancement of nitric oxide production in vasculature and the kidney. Statins have been shown to stabilize unstable plaques, improve vascular relaxation, and promote new vessel formation. Clinical trials and animal studies have shown that these agents reduce cardiovascular disease (CVD) risks and events, progression of nephropathy, development of diabetes. and fracture rates; these are benefits that go beyond lipid lowering alone. Potential beneficial effects are due to the positive impact on vascular and glomerular nitric oxide (NO) production and attenuation of vascular inflammation. Effects on bone, including fracture reduction, are thought to be mediated by direct action on bone formation. Moreover, potential reduction in the development of diabetes as observed in the West of Scotland Coronary Prevention Study (WOSCOPS) may relate to the improvement in insulin sensitivity. These actions are mediated, in part, by the effects on small G-proteins, modulation of signaling cascades, transcription, and gene expression. In particular, the inhibition of small GTP-binding proteins, Rho, Ras, and Rac, whose proper membrane localization and function are dependent on isoprenylation, may play an important role in mediating the direct cellular effects of statins on the vascular wall. The clinical relevance of these effects is beginning to be recognized, and ongoing studies will be able to answer these many questions in the near future. Actions of statins on vascular, glomerular, bone, and insulin-sensitive tissue as well as effects of statins on cognitive function and oncoprotection will be discussed in this review.