Dietary supplementation with seeds of Sesamum indicum L. (pedaliaceae) mitigates the 7,12-dimethylbenz(a)anthracene-induced breast tumor burden in rats

Objectives: Sesamum indicum L. seeds; rich in zinc and lignans are endowed with antioxidant and immunomodulatory properties which attract research on their anticancer potential. Although many studies have reported the in vitro antitumor potential of S. indicum and its phytoconstituents, much is yet to be known about its in vivo effects. To fill this gap, the effects of dietary supplementation with seeds of S. indicum in 7,12-dimethylbenz(a)anthracene-exposed rats was assessed. Methods: 42 rats aged 30-35 days were randomized into six groups (n=6) as follows: the normal (NOR) and negative (DMBA) control groups were fed with standard diet; the positive control group (DMBA + Zinc) was fed with standard diet supplemented with commercial zinc (0.01 %); the test groups were fed with standard diet supplemented with S. indicum seeds in different proportions (6.25 , 12.5 and 25 %). Breast cancer was induced by a single administration of DMBA (50 mg/kg BW, s.c.) diluted in corn oil. The experiment lasted 20 weeks and afterward, tumor incidence; tumor burden, tumor volume, tumor microarchitecture and some biochemical parameters were evaluated. Results: As salient result, 100 % of rats in the DMBA group developed tumors, while rats feed with rat chow supplemented with S. indicum seeds (25 %) had a reduced incidence of tumors (33.3 %) and tumor volume (2.71 cm3 in sesame 25 % vs. 4.69 cm3 in the DMBA group, p?0.01). The seeds (25 %) also slowed DMBA-induced neoplasm expansion in mammary ducts as compared to rats of DMBA group. Conclusions: In summary, supplementation with S. indicum seeds slowed breast tumorigenesis via its antioxidant capacity.