Simvastatin inhibits the migration and adhesion of monocytic cells and disorganizes the cytoskeleton of activated endothelial cells

Statins are powerful agents for lowering plasma cholesterol levels, which act by inhibition of the 3-hydroxy-3-methylglutaryl-CoA reductase. Evidence suggests that some of the beneficial effects may depend on their anti-inflammatory properties, due to their ability to suppress the synthesis of isoprenoids. The present study analyzes the effects of short-term simvastatin exposure on monocyte migration, cell adhesion, and endothelial cytoskeleton. We demonstrate that simvastatin completely inhibited the migration of THP-1 monocytic cells after 24 h of incubation, being prevented by coincubation with mevalonate (MVA) and geranylgeranylpyrophosphate (GGPP), but not by farnesylpyrophosphate (FPP). Simvastatin decreased chemotaxis to 70% after one hour of incubation; surprisingly neither MVA, GGPP nor FPP were able to restore the effects of the drug. Simvastatin also significantly reduced the adhesion of monocytes to interleukin-1beta (IL-1beta)-activated endothelium to 80% after preincubation for 24 h. This effect was completely reversed by coincubation with MVA and GGPP, and partially with FPP. Unexpectedly, simvastatin increased adhesion molecules expression VCAM-1 and ICAM-1 on cytokine-stimulated endothelial cells. Examination of the actin cytoskeleton on IL-1beta-activated endothelial cells showed that both 4 and 24 h of incubation with simvastatin produced a complete disappearance of F-actin, being completely restored by MVA and partially by GGPP and FPP after 24 h of coincubation. We suggest that cytoskeleton disorganization in endothelial cells is important for inhibiting monocyte adhesion, altering the adhesion molecules function. Taken together, these results strongly support the beneficial anti-inflammatory properties of statins, contributing to the overall clinical effects.