Major reduction of atherosclerosis in fractalkine (CX3CL1)-deficient mice is at the brachiocephalic artery, not the aortic root

AUTOR(ES)
FONTE

National Academy of Sciences

RESUMO

Fractalkine (CX3CL1) is of particular interest in atherogenesis because it can serve as an adhesion molecule and a chemokine. Fractalkine and its receptor CX3CR1 are expressed in atherosclerotic lesions of humans and mice. However, the effect of fractalkine deficiency on atherosclerosis susceptibility is unknown. Fractalkine-deficient mice on the C57BL/6 (B6) background were bred to the atherosclerosis-sensitizing B6.ApoE-/- and B6.LDLR-/- backgrounds. Compared with controls, aortic-root lesion area was unchanged in fractalkine-deficient male and female B6.ApoE-/- mice at 16 weeks of age and males at 12 weeks of age, but it was mildly reduced (30%, P = 0.005) in females at 12 weeks of age. In contrast, lesion area at the brachiocephalic artery (BCA) was reduced dramatically by ≈85% in fractalkine-deficient females [42,251 ± 26,136 μm2 (n = 15) vs. 6,538 ± 11,320 μm2;(n = 24), P < 0.0001] and males [36,911 ± 32,504 μm2 (n = 24) vs. 6,768 ± 8,595 μm2 (n = 14); P = 0.001] at 16 weeks of age. Fractalkine-deficient B6.ApoE-/- mice were comparable with controls in body weight, plasma cholesterol, plasma high-density lipoprotein cholesterol and white blood cell counts. On the B6.LDLR-/- background, lesion areas were reduced by 35% at the aortic root (P < 0.01) and by 50% at the BCA (P < 0.05) in fractalkine-deficient females at 16 weeks of age. Lesions in fractalkine-deficient mice on the B6.ApoE-/- and B6.LDLR-/- backgrounds were less complex and contained significantly fewer macrophages than controls. In conclusion, the major reduction of atherosclerosis in fractalkine-deficient mice appears to be at the BCA rather than the aortic root.

Documentos Relacionados