Abstract:
Antioxidants, like beta-carotene and lycopene, offer protection against radiation. The purpose of this study is to determine the efficacy of beta-carotene and lycopene as radioprotectants after administration of certain doses of the test substances. All groups of mice were acclimatized for seven days and were given food pellets and water ad libitum. Group 1 mice were treated with beta-carotene; group 2 mice with lycopene. Vegetable oil was mixed with the test substances to facilitate their absorption. Group 3 served as the positive (irradiated) control, while group 4 served as the negative (unirradiated) control. Treatment period lasted for five days. Group 1 to 3 were subjected to a single exposure of 5 Gy gamma radiation. All mice were sacrificed three days after the exposure, and the upper duodenum was excised and mounted on microscope slides for histological analysis. The mucosal thickness was measured and viable crypts were counted. Unirradiated mice showed the greatest value for average mucosal thickness (0.431 mm), and average number of viable crypts (18); followed by lycopene treated mice (average mucosal thickness is 0.419 mm; average number of viable crypts is 16); followed by beta-carotene treated mice (average mucosal thickness is 0.38 mm; average number of viable crypts is 13); and finally by the positive (irradiated) control (average mucosal thickness is 0.158 mm; average number of viable crypts is 7). Based on the results, exposure to 5Gy gamma radiation caused damage on duodenal mucosa, but beta-carotene and lycopene reduced the damaging effects of radiation. Higher mean values for both mucosal thickness and number of viable crypts for the lycopene treated mice showed that lycopene is a better radioprotectant than beta-carotene.
