Synergetic effect of desialylated and glycated low density lipoproteins on cholesterol accumulation in cultured smooth muscle intimal cells.

We have studied the combined effect of non-enzymatically glycosylated and desialylated low density lipoproteins (LDL) on the cholesterol content of cells cultured from unaffected human aortic intima. Native LDL did not alter the intracellular cholesterol level while glycated LDL taken in the concentration percent, respectively. The effect of the same concentrations of glycated LDL treated with neuraminidase (desialylated-glycated LDL) was twice as powerful. Desialylated LDL in the concentration of 50 and 100 micrograms/ml raised the cholesterol level by 1.4- and 2.1-fold, respectively. Simultaneous incubation of cells with glycated (50 micrograms/ml) and desialylated (50 micrograms/ml) LDL brought about a 3.4-fold increase in intracellular cholesterol. The obtained data suggest that intensive development of atherosclerosis in diabetes mellitus may be partially explained by synergetic effects of desialylated and glycated lipoproteins as well as LDL with both types of modification.