An HMG-CoA reductase inhibitor, cerivastatin, suppresses growth of macrophages expressing matrix metalloproteinases and tissue factor in vivo and in vitro.
BACKGROUND
Unstable atherosclerotic plaques that cause acute coronary events usually contain abundant macrophages expressing matrix metalloproteinases (MMPs) and tissue factor (TF), molecules that probably contribute to plaque rupture and subsequent thrombus formation. Lipid lowering with HMG-CoA reductase inhibitors reduces acute coronary events.


RESULTS
To test whether lipid lowering with an HMG-CoA reductase inhibitor retards macrophage accumulation in rabbit atheroma, we administered cerivastatin to immature Watanabe heritable hyperlipidemic rabbits (cerivastatin group, n=10, cerivastatin 0.6 mg x kg(-1) x d(-1); control group, n=9, saline 0.6 mL x kg(-1) x d(-1)) for 32 weeks and measured macrophage accumulation and expression of MMPs and TF. Serum cholesterol levels after 32 weeks were 809+/-40 mg/dL (control group) and 481+/-24 mg/dL (treated group). Cerivastatin diminished accumulation of macrophages in aortic atheroma. Macrophage expression of MMP-1, MMP-3, MMP-9, and TF also decreased with cerivastatin treatment. Cerivastatin reduced the number of macrophages expressing histone mRNA (a sensitive marker of cell proliferation) detected by in situ hybridization but did not alter macrophages bearing a marker of death (TUNEL staining). Cerivastatin treatment (>or=0.01 micromol/L) also reduced growth, proteolytic activity due to MMP-9, and TF expression in cultured human monocyte/macrophages.


CONCLUSIONS
These results suggest that lipid lowering with HMG-CoA reductase inhibitors alters plaque biology by reducing proliferation and activation of macrophages, prominent sources of molecules responsible for plaque instability and thrombogenicity.
Aikawa
M
M
Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. maikawa@rics.bwh.harvard.edu
Rabkin
E
E
Sugiyama
S
S
Voglic
S J
SJ
Fukumoto
Y
Y
Furukawa
Y
Y
Shiomi
M
M
Schoen
F J
FJ
Libby
P
P
D000818:Animals; D001161:Arteriosclerosis / Q000378:metabolism* / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D008264:Macrophages / Q000378:metabolism* / Q000473:pathology*; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology*; D011817:Rabbits; D013925:Thromboplastin / Q000378:metabolism*
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D011725:Pyridines; D013925:Thromboplastin; C086276:cerivastatin; D020782:Matrix Metalloproteinases; D019278:Matrix Metalloproteinase 3; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1