Blueberry diet protect against atherosclerosis in apoE‐deficient mice by inhibiting scavenger receptor expression

Atherosclerosis is an inflammatory process that leads to the onset of cardiovascular disease. Recently we reported that apoE knockout (apoE −/− ) mice fed AIN‐93G diet (control) formulated to contain 1% freeze‐dried whole wild blueberries (BB) were found to have significantly less oil red O positive fatty streak atherosclerotic lesions in aorta. The scavenger receptor‐mediated uptake of oxidized‐LDL (oxLDL) by macrophages leads to foam cell formation, which is an initial event in the formation of atherosclerotic fatty streak lesions. We hypothesize that the atheroprotective effect of BB is mediated by inhibition of scavenger receptor expression. The mechanism contributing to the atheroprotective effects of blueberry‐supplemented diet was addressed in apoE−/− mice. Reduced mRNA expression of scavenger receptors (CD36, scavenger receptor A and CD68) in proximal aorta was found in BB fed group compared to control diet‐fed mice. Further, protein levels of scavenger receptors in aorta as well as macrophages were also reduced in mice fed BB diet compared with control diet. These findings suggest that the atheroprotective effect of the BB supplemented diet is mediated in part by inhibiting scavenger receptor expression that could result in reduced oxLDL uptake leading to fatty streak lesions, an early event of atherogenesis. USDA‐CRIS‐6251‐5100002‐06S .