No abstract

No abstract

No abstract

Background. Some natural carotenoids have anti-carcinogenic, anti-mutagenic, and immunomodifying activity and may be considered as potential agents for chemoprevention of cancer. Objective: to study pharmacokinetics of beta-carotene, cantaxantene, lycopene, and carotene-containing compounds created on the base of the mentioned substances. Materials and methods. The study used carotene-containing drugs, which we previously created, such as Betask, Kaskatol, Tomatol, natural carotene-tocopherol complex derived from cankerberry. The research was conducted on mice, rats, rabbits, dogs, piglets, monkeys (Javanese macaque); the observations also involved healthy donors and patients with colorectal cancer before surgery. Carotenoid and retinoid detection was made by high performance liquid chromatography in blood plasma and liver tissue. Results. Comparative analysis of pharmacokinetics of the studied carotenoids demonstrates their relatively low absorption in animals. Bioavailability varies significantly among species; and it increases in the following order: dogs, rabbits, mice, rat, piglets, humans. Pharmacokinetics of carotenoids and carotene-containing compounds was studied with single and multiple administration per os. Cantaxantene and lycopene have a better bioavailability as compared to synthetic beta-carotene. Pharmacokinetics of synthetic carotenes and carotenoids of carotene-containing compounds has no significant differences. Beta-carotene in natural carotene-tocopherol complex has higher bioavailability (2-4 fold higher) as compared to synthetic beta-carotene. Regular complex administration into monkeys results in enhanced beta-carotene levels in blood serum of the animals and inhibits chemically induced carcinogenesis. The patients’ intake of beta-carotene in the pre-operational period was associated with the enhanced pro-vitamin levels in blood serum and stimulation of a number of cellular immune parameters. Conclusions. The studied carotenoids and carotene-containing compounds may be used in combined antitumor therapy and as treatment and prophylactics agents in cancer risk groups.

No abstract