Introduction : Skin cancer is one type of cancer which the number of the patient increases from year to year. Cocoa has powerful antioxidant content, such as flavonoids, catechins, epicathechin and proanthocyanidin which in a previous study showed protective effects against cancer. Carcinogenic agents induce the release of reactive oxygen species (ROS), which damage DNA, RNA and reacted with fatty acids in the cell membrane then forming malondialdehyde (MDA) at the initiation phase. In malignancy, the excessive expression of Bcl-2 can be found as one of at the initiation phase of carcinogenesis.
Objective : To determine the differences in MDA levels, Bcl-2 tissue expression between control mice and mice that applied DMBA and topical cocoa extract with different concentrations.
Method : The study sample was 30 Swiss albino mice, divided into 6 groups of 5 mice each: Group I without treatment, group II DMBA, III cacao 200 ppm and DMBA, IV cocoa 400 ppm and DMBA, V cocoa 800 ppm. Cocoa extract was applied everyday followed by DMBA with 1 day interval, all for 1 week.
Result : In the experiment group, the lowest level of MDA is in the 200 ppm cocoa group (p ≤ 0.05). MDA level is increasing along with cocoa concentration, however at the highest cocoa concentration 800 ppm the average of MDA level is still lower than the DMBA group. Bcl-2 expression was shown in 60% of the subjects in the DMBA group, 40% of the subjects in the 200 ppm cocoa group, 20% in the 400 ppm and 800 ppm cocoa group.
Conclusion : Topical application of cocoa extract has a protective effect in the initiation phase because there is a decrease in MDA levels at a concentration of 200 ppm. The expression of Bcl-2 decreased along with the increasing concentration of cocoa extract.
Key words: Cocoa extract, Bcl-2, DMBA, MDA
|
