Malondialdehyde affects the physico-chemical and biological characteristics of oxidized low density lipoprotein

Oxidized LDL (Ox-LDL) was found in the atherosclerotic lesion and was associated with the formation of foam cells. Ox-LDL (30 micrograms protein/ml) reduced collagen induced platelet aggregation by 18% but following dialysis, this lipoprotein enhanced platelet aggregation by 21% in platelet-rich plasma. The addition of malondialdehyde to the dialyzed Ox-LDL prevented its stimulatory activity. Enhanced macrophage uptake of Ox-LDL however, was not affected by dialysis. Thus it is important to use similar preparations of Ox-LDL when comparing results with these lipoproteins.