Poly(ADP-Ribose) Polymerase Inhibition Reduces Atherosclerotic Plaque Size and Promotes Factors of Plaque Stability in Apolipoprotein E–Deficient Mice Effects on Macrophage Recruitment, Nuclear Factor-κB Nuclear Translocation, and Foam Cell Death

Background— Poly(ADP-ribose) polymerase (PARP) was suggested to play a role in endothelial dysfunction that is associated with a number of cardiovascular diseases. We hypothesized that PARP may play an important role in atherogenesis and that its inhibition may attenuate atherosclerotic plaque development in an experimental model of atherosclerosis. Methods and Results— Using a mouse (apolipoprotein E [ApoE]−/−) model of high-fat diet–induced atherosclerosis, we demonstrate an association between cell death and oxidative stress–associated DNA damage and PARP activation within atherosclerotic plaques. PARP inhibition by thieno[2,3-c]isoquinolin-5-one reduced plaque number and size and altered structural composition of plaques in these animals without affecting sera lipid contents. These results were corroborated genetically with the use of ApoE−/− mice that are heterozygous for PARP-1. PARP inhibition promoted an increase in collagen content, potentially through an increase in tissue inhibitor of metallopr...