Plasma and hepatic antioxidant control and vitamin A nutritional status.
Twenty-seven rats were divided into three groups and fed on diets containing 0.3, 6 or 60 RE (retinol equivalent) retinyl palmitate/g food. After 7 weeks, hepatic vitamin A uptake was found to be more efficient in vitamin A-deficient rats than in rats given adequate vitamin A. We showed that during the metabolic adaptation of the animals to the level of vitamin A in the diet, extensive modifications occur in the antioxidant defences of the organism. In parallel with the increase in the level of vitamin A, the decrease in the level of alpha-tocopherol in the plasma can bring about a greater susceptibility of the lipoproteins to oxidative stress. Similarly, the decrease in the hepatic alpha-tocopherol level and in glutathione peroxidase activity leads to the weakening of the liver's antioxidant defences.
Subirade
I
I
Laboratoire des Xénobiotiques, I.N.R.A., Toulouse, France.
Fernandez
Y
Y
Périquet
B
B
Mitjavila
S
S
Anglade
F
F
Périquet
A
A
D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D004032:Diet; D004224:Diterpenes; D005979:Glutathione Peroxidase / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D009752:Nutritional Status; D051381:Rats; D017207:Rats, Sprague-Dawley; D000084562:Retinyl Esters; D014801:Vitamin A / Q000008:administration & dosage* / Q000031:analogs & derivatives / Q000097:blood* / Q000378:metabolism; D014810:Vitamin E / Q000097:blood / Q000378:metabolism
D000975:Antioxidants; D004224:Diterpenes; D000084562:Retinyl Esters; D014801:Vitamin A; D014810:Vitamin E; C014794:retinol palmitate; D005979:Glutathione Peroxidase