Total Antioxidants Status, Selenium Concentration, Catalase and Glutathione Peroxidase Activities in Rabbits Fed a High-Garlic Diet

Aim: Results from previous studies on the effects of intake of garlic on the body antioxidant system
appear inconclusive. This study measured glutathione peroxidase (GPx) and catalase (CAT)
activities, Total Antioxidant Status (TAS) and selenium (Se) level in rabbits fed a high-garlic diet.
Methods: Ten rabbits randomly assigned into two groups (group 1=control and group 2= test) of five
rabbits each were used for the experiment. The diet of group 2 was mixed with raw garlic homogenate
(1.75g/Kg body weight/day) for 4 weeks. Two sets of blood samples were collected from each animal
at the beginning of the experiment (baseline) and at the end (4 weeks). Blood samples were analyzed
for blood GPx and serum CAT activities and TAS by spectrophotometric methods while Se was
determined using Atomic Absorption Spectrophotometric (AAS) method.
Results: At baseline, means of the parameters measured did not differ significantly between groups 1
and 2. At the 4th week, means of TAS (1741.20±381.53 μmol Trolox equiv/L), Se (47.20±12.22 μg/dl),
CAT activity (273.20±68.05 U/L) and GPx activity (12392.00±3068.34 U/L) in the test group were
significantly higher than means of the corresponding control group (820.20±91.94 μmol Trolox
equiv/L, 20.80±1.92 μg/dl, 145.40±13.35 U/L, 8528.00±1757.59 U/L, respectively). There were
positive associations between CAT and GPx (r = 0.65, p<0.01) activities, CAT and TAS (r = 0.77,
p<0.01), GPx and TAS (r = 0.66, p<0.01) and Se and TAS (r = 0.70, p<0.01).
Conclusion: Results from this present study suggest that significant increases observed in the
activities of antioxidant enzymes, Se level and TAS could possibly be associated with consumption of
high garlic diet by the rabbits. Overall, the significant increase in the CAT and GPx activities as well as
the levels of Se and TAS seen in the test group at the end of the study suggests that consumption of
raw garlic extract could result to increases in the activities of important antioxidant enzymes and
improve the total antioxidant status of the body of rabbits.