Oxidatively modified very low density lipoprotein enhances monocyte adhesion to endothelial cells

Abstract

Very low density lipoprotein (VLDL) was incubated with CuCl₂(10 (μmol/ L) at room temperature for 24 hours. The thiobarbituric acid reactive substance (TBARS) was much higher and the electrophoretic mobility was much faster in VLDL after incubation with CuCl₂ than that in VLDL without incubation with CuCl₂. It demonstrated that VLDL was oxidatively modified by Cu²⁺. Endothelial cells were pretreated with normal VLDL (N-VLDL) and oxidatively modified VLDL (O-VLDL) and then the adhesion of monocyte to endothelial cells was assayed. We observed that O-VLDL at all the concentrations used enhanced monocyte adhesion to endothelial cells significantly. The results suggest that oxidative modification of VLDL may play a role in the early stage of atherogenesis by increasing monocyte adhesion to endothelial cells.

Keywords

oxidative modification / VLDL / monocyte / endothelial cells / adhesion

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