Lycopene most likely contributes to the positive health effects of tomatoes on the cardiovascular system. However, elucidation of underlying cellular mechanisms is hampered by the intricate solubility of lycopene in aqueous solutions. Cells relevant to the cardiovascular system, including bovine aortic endothelial cells (BAECs), the monocytic cell line THP-1, and RAT-1 fibroblasts, were treated for various time periods (0–72 h) with different concentrations of lycopene (1, 5, and 10 µM), solubilized either in tetrahydrofuran (THF) or micelles as solvents. Incubation of all three cell types led to a concentration- and time-dependent increase in cellular lycopene content. Both vehicles tested, THF and micelles, proved equally effective in the delivery of lycopene to cells. A marked difference in the amount of lycopene incorporated was observed among the various cell types. Compared with THP-1 cells, the uptake of lycopene using both solvents was higher in BAECs and RAT-1 fibroblasts for all concentrations and time points tested.
Epidemiological data indicate a beneficial effect for consumption of tomato products in the prevention of cardiovascular diseases. Only limited data are available on the cellular uptake of lycopene in vascular cells. Lycopene was successfully delivered to different cells relevant for the cardiovascular system. These results represent an important prerequisite for the study of molecular and cellular mechanisms by which lycopene may exert its beneficial effects on the cardiovascular system.