Sparing effects of selenium and ascorbic acid on vitamin C and E in guinea pig tissues.
BACKGROUND
Selenium (Se), vitamin C and vitamin E function as antioxidants within the body. In this study, we investigated the effects of reduced dietary Se and L-ascorbic acid (AA) on vitamin C and alpha-tocopherol (AT) status in guinea pig tissues.


METHODS
Male Hartley guinea pigs were orally dosed with a marginal amount of AA and fed a diet deficient (Se-D/MC), marginal (Se-M/MC) or normal (Se-N/MC) in Se. An additional diet group (Se-N/NC) was fed normal Se and dosed with a normal amount of AA. Guinea pigs were killed after 5 or 12 weeks on the experimental diets at 24 and 48 hours post AA dosing.


RESULTS
Liver Se-dependent glutathione peroxidase activity was decreased (P < 0.05) in guinea pigs fed Se or AA restricted diets. Plasma total glutathione concentrations were unaffected (P > 0.05) by reduction in dietary Se or AA. All tissues examined showed a decrease (P < 0.05) in AA content in Se-N/MC compared to Se-N/NC guinea pigs. Kidney, testis, muscle and spleen showed a decreasing trend (P < 0.05) in AA content with decreasing Se in the diet. Dehydroascorbic acid concentrations were decreased (P < 0.05) in several tissues with reduction in dietary Se (heart and spleen) or AA (liver, heart, kidney, muscle and spleen). At week 12, combined dietary restriction of Se and AA decreased AT concentrations in most tissues. In addition, restriction of Se (liver, heart and spleen) and AA (liver, kidney and spleen) separately also reduced AT in tissues.


CONCLUSIONS
Together, these data demonstrate sparing effects of Se and AA on vitamin C and AT in guinea pig tissues.
Bertinato
Jesse
J
Nutrition Research Division, Food Directorate, Health Products and Food Branch, Health Canada, Sir Frederick G, Banting Research Centre, Ottawa, ON, Canada. jesse_bertinato@hc-sc.gc.ca
Hidiroglou
Nick
N
Peace
Robert
R
Cockell
Kevin A
KA
Trick
Keith D
KD
Jee
Penny
P
Giroux
Alex
A
Madère
Réné
R
Bonacci
Giuseppe
G
Iskandar
Monica
M
Hayward
Stephen
S
Giles
Nicholas
N
L'Abbé
Mary R
MR
D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism* / Q000494:pharmacology*; D005978:Glutathione / Q000097:blood; D005979:Glutathione Peroxidase / Q000187:drug effects / Q000378:metabolism; D006168:Guinea Pigs; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D023421:Models, Animal; D012643:Selenium / Q000494:pharmacology*; D014810:Vitamin E / Q000378:metabolism*
D014810:Vitamin E; D005979:Glutathione Peroxidase; D005978:Glutathione; D012643:Selenium; D001205:Ascorbic Acid