Fig. 1

Tar promoted atherosclerotic plaque progression in ApoE^−/− mice. A Starting at 8 weeks, ApoE^−/− mice were fed with high-fat diet and intraperitoneal injected with saline or cigarette tar (40 mg/kg/day) for 16 weeks. n = 20. B Representative images and quantification of Oil Red O staining in descending aorta. Scale bar: 2 mm. n = 8. C Representative images and quantification of Oil Red O staining in the aortic root. Scale bar: 200 μm. n = 8. D Representative images of HE in the aortic root lesions. The position in the dashed rectangular box is enlarged as shown below. Circled by the irregular dotted line is the necrotic core. E Representative images of Masson staining. Outlined by the irregular dotted line shows the fibrous cap. n = 8. F Representative images of α-SMA (VSMCs) immunofluorescence staining in the brachiocephalic artery of mice. The upper left corner is an enlargement of the image in the dashed rectangular. Scale bar: 200 μm. n = 8. G Representative images of TUNEL staining in aortic root plaques of mice. Scale bar: 100 μm. n = 8. H Representative images of Ki67 (green), α-SMA (red) staining in the aortic root, and quantification of Ki67⁺α-SMA⁺ cells in total α-SMA⁺ cells. Scale bar: 100 μm. n = 8. Data were expressed as mean ± SD. *p < 0.05, **p < 0.01, ***p < 0.001