Modulation of low-density lipoprotein-induced inhibition of intercellular communication by antioxidants and high-density lipoproteins.

ABSTRACT

In order to study the capacity of antioxidants and high-density lipoproteins (HDL) to modulate the effects of low-density lipoprotein (LDL) on intercellular communication, arterial smooth muscle cells and a dye transfer method were used. LDL, in contrast to HDL, inhibited the communication between arterial smooth muscle cells from human umbilical cord and thoracic aorta in a dose-dependent manner. LDL, which can be oxidized, as detected by the lipid-peroxidation assay and gel electrophoresis, did not influence cell-cell communication in the presence of the antioxidants butylated hydroxytoluene (BHT), alpha-tocopherol and glutathione. The results suggest that LDL must undergo oxidative modification before it can influence intercellular communication. Like antioxidants, HDL diminished the LDL-induced inhibition of cell-cell communication. This study suggests that the modulation of gap-junctional communication by the balance of HDL and LDL in plasma may influence atherogenesis.