Oxidized low-density lipoprotein induces the production of superoxide by neutrophils.

Exposure of guinea pig peritoneal neutrophils to ox-LDL led to the production of superoxide, which was measured by the formation of superoxide-dependent chemiluminescence. The cells exposed to unoxidized LDL, e.g. native LDL, acetyl-LDL, and self-aggregates of LDL showed no production of superoxide. The superoxide production was correlated with the levels of oxidative modification of LDL and reached a maximum between 10 and 30 min during incubation, but preincubating the cells with cytochalasin B decreased the superoxide production. These findings indicate that neutrophils rapidly take up ox-LDL by phagocytosis and generate superoxide which may cause superoxide-mediated lipid peroxidation in vivo.