Abstract
Macrophage-derived foam cells play an important role in atherosclerotic lesions. Oxidized low-density lipoprotein (OxLDL) induces macrophage proliferation via the specific uptake of lysophosphatidylcholine (LysoPC) of OxLDL by class A, type I and type II macrophage scavenger receptors. We have previously shown that Asp-hemolysin from Aspergillus fumigatus binds to LysoPC as a typical lipid moiety of OxLDL. This study investigated the effect of the Asp-hemolysin-related peptide (P-21), a synthetic peptide derived from a region of Asp-hemolysin that is rich in positive charges, on macrophage proliferation induced by OxLDL. Mouse peritoneal macrophages were used for proliferation study. OxLDL induced macrophage proliferation in an oxidation time-dependent manner, and P-21 inhibited OxLDL-induced macrophage proliferation in a dose-dependent manner. Furthermore, the binding analysis of P-21 to OxLDL by dissociation-enhanced lanthanide fluorometric immunoassay indicated that P-21 binds to OxLDL. These results indicate that P-21 inhibits the OxLDL-induced macrophage proliferation through binding of P-21 to OxLDL.
