Increased IL-37 in Atherosclerotic Disease could be Suppressed by Atorvastatin Therapy

Recently, the evidence showed that interleukin-37 (IL-37) was expressed in the foam-like cells of atherosclerotic coronary and carotid artery plaques in IL-37-transgenic mice, suggesting that interleukin-37 is involved in atherosclerosis-related diseases. The purpose of this study was to determine the change of IL-37 in atherosclerotic plaque, the effect of atorvastatin on IL-37 and the association between IL-37 and Smad3 in atherosclerotic disease. Rabbits were subjected to atherosclerosis by the immunologic injury composite with balloon injury (BI). Some rabbits received atorvastatin treatment from 6 weeks to 12 weeks. Serum levels of IL-37 were assessed at baseline, 6 weeks and 12 weeks in normal, atherosclerotic and atorvastatin groups. Protein and RNA levels of IL-37 atherosclerotic plaque from abdominal aorta were processed at 12 weeks. Abdominal aorta including atherosclerotic plaque was immunostained with IL-37 and Smad3. Serum IL-37 significantly increased in atherosclerotic disease, and this increase could be reduced by the atorvastatin treatment. IL-37 and Smad3 were accumulated in the macrophage-derived foam cells in the plaque and significantly increased in protein and RNA levels. Atorvastatin treatment could significantly suppress the increase of both IL-37 and Smad3. Plasma level of IL-37 and the IL-37 expression of the plaque were significantly increased in atherosclerotic disease. This increase could be suppressed by the atorvastatin treatment. In addition, Smad3 might be required for IL-37 activity during the atherosclerotic physiologic process.