Fig. 7

Quantitation of aortic atherosclerosis at 16 weeks after HFFD feeding. a Representative pictures of aortas stained by Sudan IV are shown on the left. The lesion area (defined by sudanophilic staining as red) was quantified using an image analysis system (right). Data are expressed as the mean ± SD. n = 5 for each group. **P < 0.01 vs. the control group. b Representative micrographs of the aortic arch lesions from each group. Serial paraffin sections were stained with hematoxylin-eosin (HE) and elastica van Gieson (EVG) or immunohistochemically stained with mAbs against either macrophages (Mϕ) or α-smooth muscle actin for smooth muscle cells (SMCs). Histologically, there are two types of lesion: (1) early-stage lesions (fatty streaks) are mainly composed of foam cells as shown at 8 weeks above (top); and (2) advanced lesions are characterized by the formation of lipid core or necrotic cores covered by a fibrous cap. In addition, calcification is often seen (middle and bottom indicated by arrowheads). c Quantitation of aortic arch lesions, macrophages and smooth muscle cells, the early stage lesions, and advanced lesions. Data are expressed as the mean ± SD. n = 5 for each group. *P < 0.05 vs. the control group