Abstract:

Objective: To compare the effects of organic selenium such as L-Se-methylselenocysteine (Se-SMC) and inorganic
selenium (sodium selenite) on antioxidant functions in rats, and explore the synergistic effect of Se-SMC and vitamin E (VE)
on antioxidant functions in vivo. Methods: Adult female rats were randomly divided into five groups including blank group,
organic selenium group, inorganic selenium group, VE group, and organic selenium/VE combination group. The rats were
administrated with designed drugs by gavage for 30 d. The serum levels of malonaldehyde (MDA) content, total antioxidant
activity (T-AOC) and superoxide dismutase (SOD) activity in the rats were determined at 10, 20 d and 30 d, respectively. After
30 d, the rats were sacrificed, and MDA, glutathione (GSH) and protein carbonyl (CP) contents, and T-AOC level, as well as
SOD and glutathion peroxidase (GSH-Px) activities were determined in the heart, liver and kidney of the rats. Results: Se-
SMC resulted in higher GSH-Px activity than inorganic selenium in rat tissues. The combination of organic selenium and VE
significantly enhanced T-AOC and SOD activities in the serum of rats after administration for 20 d and 30 d and elevated T-AOC
and SOD activities as well as GSH-Px and GSH contents in the heart, liver and kidney of rats. Conclusion: Organic selenium is
better than inorganic selenium for enhancing GSH-Px activity in heart, liver and kidney tissues. In addition, the combination of
organic selenium and VE can enhance antioxidant functions in rats.

Key words: organic selenium, inorganic selenium, VE, combination, rats, antioxidant activity