Carotenoids inhibit DNA synthesis in human aortic smooth muscle cells

Quiescent, serum-starved human aortic smooth muscle cells were restimulated with 20% foetal calf serum in Dulbecco's modified Eagle medium, in the pre sence and absence of p-carotene, canthaxanthin, zeaxanthin, lycopene, lutei n or beta-cryptoxanthin, at final concentrations up to 23 mu M. Concentrati on-dependent inhibition of DIVA synthesis, measured by [methyl-H-3]thymidin e incorporation, was observed for the carotenoids, except for canthaxanthin and lutein which had no effect. Lycopene was the most potent of the carote noids tested. The results suggest that antiproliferative effects of dietary carotenoids might be of significance in vivo. (C) 1999 Federation of Europ ean Biochemical Societies.