Figure 4.

6-Phophofructo-2-kinase/fructose-2,6-biphosphatase (PFKFB3) expression is increased in murine vessels upon Lp(a) (lipoprotein(a)) stimulation. A, Representative images of murine WT (wild type) aortas ex vivo stimulated with (lower images; n=5) and without (upper images; n=6) 100 mg/dL Lp(a) stimulation. Nuclei were stained with DAPI (4′,6-diamidino-2-phenylindole; blue); ECs are stained with PECAM-1 (platelet endothelial cell adhesion molecule 1; red), PFKFB3 (green), and ICAM (intercellular adhesion molecule)-1 (magenta; 18 h incubation; white bar=200 μm). B, Quantification of A. Data were analyzed using 2-tailed Student unpaired t test, P=0.0004. C, Representative images of aortas derived from Lp(a) mice [Lp(a)-Tg; n=4] and mice lacking the lysine-binding site, which, therefore, cannot carry oxidized phospholipids (LBS-Lp(a)-Tg; n=6) stained for PECAM-1 (red) and PFKFB3 (green); nuclei were stained with DAPI (blue; white bar=200 μm). D, Quantification of C; EC PFKFB3 expression in aortas of Lp(a)-Tg and LBS-Lp(a)-Tg mice on a chow diet. Data were analyzed using 2-tailed Student unpaired t test, P=0.0354. E, Images representing human carotid plaques derived from patients with low Lp(a) vs high Lp(a) levels. Nuclei were stained with DAPI (blue); ECs are stained with vWF (von Willebrand factor; red), PFKFB3 (green), and ICAM-1 (magenta; n=6 per group; white bar=200 μm). F, Quantification of E. Data were analyzed using 2-tailed Student unpaired t test; for PFKFB3, P=0.0206; for ICAM-1, P=0.0134. All data are mean±SEM. *P<0.05, ***P<0.0005.