Benzoporphyrin derivative decreases the binding of low density lipoprotein to the glycosaminoglycan chondroitin-6-sulfate in vitro

We have investigated the effect of the hydrophobic photosensitizer (PS), benzoporphyrin derivative (BPD), on low density lipoprotein (LDL) binding to the glycosaminoglycan (GAG), chondroitin-6-sulfate (C-6-S) in vitro. Agarose electrophoresis of the BPD-LDL complexes indicated that ratios of 50 ng BPD per μg LDL protein and above displayed increased net negative charge. Ratios less than 10 ng BPD per μg LDL protein slightly increased the association of the LDL with the C-6-S. Ratios of 10 ng BPD per μg LDL protein and greater decreased the association between LDL and GAG in a BPD concentration dependent manner. Since the retention of LDL by the extracellular matrix (ECM) GAG in the artery wall is a key event in atherogenesis, the reported effects of BPD on LDL binding to C-6-S may be of interest.