INDUCTION OF HUMAN ENDOTHELIAL-CELL GROWTH BY MILDLY OXIDIZED LOW-DENSITY-LIPOPROTEIN

The aim of the present study was to examine whether endothelial growth could be modulated by mildly oxidized low density lipoprotein. When h uman endothelial cells were cultured in the presence of mildly oxidize d low density lipoprotein (1 mu g/ml), a significant induction of endo thelial cell growth was observed, whereas native low or high density l ipoprotein were ineffective. Further, treatment of endothelial cells w ith mildly oxidized low density lipoprotein modulated the expression o f cytokines and growth factors which may be relevant in atherogenesis. Endothelial cells chronically exposed to mildly oxidized low density lipoprotein underwent a more rapid onset of cellular senescence. Since senescence is associated with endothelial dysfunction, the novel find ing showing that mildly oxidized low density lipoprotein induces endot helial cell growth may be relevant in the development and evolution of the atherosclerotic lesions.