Amelioration of Skin cancer in mice by β-carotene and Phenolics of Carrot (Daucus carota).

Carrot (Daucus carota) is a widely used nutritional source and is rich in β-carotene.
Our previous work highlights the potential anticancer properties of phenolics from
various dietary sources. The current study is designed to understand the relative
levels of phenolics and β-carotene and their contribution to antioxidant (AOX),
tyrosinase inhibitory (TI) and antiproliferative (AP) properties in UV-DMBA induced
skin cancer in mice. Phenolic fractions of carrot - free (CRFP) and bound (CRBP) and
β-carotene were extracted and quantitated by HPLC. AOX, TI and AP capacities of each
of the phenolic acids of CRFP / CRBP and β-carotene were determined. DMBA followed
by UV treatment was employed to induce skin cancer in mice. Different doses of CRFP,
CRBP and β-carotene were evaluated for anticancer potency using tumor index,
biochemical parameters and tumor markers in various groups of animals. Although
same levels of β-carotene were present in CRFP and CRBP, a higher reduction in tumor
formation (~ 2 folds), tyrosinase (~5 folds), galectin-3 (~18 folds) and increased
antioxidant levels (~1-3 folds) in CRFP rather than in CRBP suggests that, in addition
to β-carotene, the nature of other phenolic acids in CRFP do play a key role in
anticancer property. Thus carrot with enriched levels of phenolics and β-carotene
may be efficient in the prevention of skin cancer as evidenced by in vitro and in vivo.