Serum carotenoids in relation to risk factors for development of atherosclerosis

To explore associations between serum carotenoids and risk factors for development of atherosclerosis.

We studied 40 early atherosclerosis patients without clinical cardiovascular events and comparable healthy controls aged 45-68 years. Intima-media thickness (IMT) and arterial stiffness were simultaneously measured by carotid ultrasonography, and serum carotenoids and cytokines were determined by high-pressure liquid chromatograph (HPLC) and ELISA kits respectively. We evaluated the associations between serum carotenoids, early atherosclerosis and serum cytokines.

Serum concentrations of lutein and zeaxanthin in early atherosclerosis patients were significantly lower than those of control subjects. PCA logistic analysis found that serum carotenoids were associated with decreased risk of atherosclerosis. In contrast, blood pressure, body mass index and serum triglyceride were positively related to the risk of atherosclerosis. Ridge regression analysis revealed that serum carotenoids were associated with inflammatory cytokines and apoE. More specifically, serum lutein was inversely associated with IL-6 (P<0.001) and positively associated IFN-γ (P=0.002). In contrast, zeaxanthin had a significant negative association with VCAM-1 (P=0.001) and apoE (P=0.022) .Lycopene was inversely associated with VCAM-1(P=0.011) and LDL (P=0.046).

The results suggested that early atherosclerosis patients had lower serum concentrations of lutein and zeaxanthin than healthy subjects. Serum carotenoids were associated with reduced risk of atherosclerosis. The associations between serum carotenoids and inflammatory cytokines may help to explain the possible protective effects of carotenoids on atherosclerosis.