Aggregated LDL in contact with macrophages induces local increases in free cholesterol levels that regulate local actin polymerization.

ABSTRACT:

Objective

Interaction of macrophages with aggregated matrix-anchored lipoprotein deposits is an important initial step in atherogenesis. Aggregated lipoproteins require different cellular uptake processes than those used for endocytosis of monomeric lipoproteins. In this study, we tested the hypothesis that engagement of aggregated LDL (agLDL) by macrophages could lead to local increases in free cholesterol levels and that these increases in free cholesterol regulate signals that control cellular actin.

Methods and results

AgLDL resides for prolonged periods in surface-connected compartments. Although agLDL is still extracellular, we demonstrate that an increase in free cholesterol occurs at sites of contact between agLDL and cells because of hydrolysis of agLDL-derived chol

SUBMITTER: Grosheva I 

PROVIDER: S-EPMC2755184 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature