Saraca asoca (Family Caesalpiniaceae) has been widely used in traditional Indian medicine especially due to its wound-healing property. The present study investigates the chemopreventive property of
flavonoids from Saraca asoca (flowers) on 2-stage skin
carcinogenesis in mice models.
Skin cancer was induced in Swiss albino mice by single topical application of 7,12-dimethyl
benzanthracene (100 µg/50 µL of
acetone) followed by thrice a week treatment of
croton oil for 20 weeks. The topical pretreatment of the
flavonoid fraction from S asoca (FF S asoca) was 30 minutes prior to the application of
croton oil thrice weekly for 20 weeks. At the end of the experimental period the animals were sacrificed, and the
tumor statistics and various marker parameters were studied (
enzyme assays, Western blotting). The pretreatment of the FF of S asoca caused significant reduction in the number of
tumors per mouse and the percentage of
tumor-bearing mice. Also, the latency period for the appearance of the first
tumor was delayed by S asoca pretreatment. In plant-treated animals there was a significant increase in the levels of
reduced glutathione,
catalase, and
protein in skin when compared with the untreated animals. Conversely, there was a significant decrease in the lipid peroxidation levels. A significant reduction in the expression of
ornithine decarboxylase, a key
enzyme in the promotion stage of 2-stage
skin cancer, in the plant-treated group was also observed. These findings suggest the chemopreventive activity of
flavonoids from S asoca on 2-stage skin
carcinogenesis.