A. Martin et al., Effect of vitamin E intake on levels of vitamins E and C in the central nervous system and peripheral tissues: implications for health recommendations, BRAIN RES, 845(1), 1999, pp. 50-59
Vitamin E (alpha-gamma-tocopherol) is an important component in biological
membranes. A decrease in its concentration imposes structural and functiona
l damage to the cells. The object of this study was to assess the effect of
a graded dietary vitamin E (E) intake on E concentration in specific regio
ns of the brain, and its influence on Vitamin C levels and neurological fun
ction. Following a 2-month period, rats supplemented with 5, 30, 60, 250 or
500 mg all-rac-alpha-tocopherol-acetate/kg diet (mg E/kg diet) exhibited a
significant increase of E concentration in brain and peripheral tissues. H
owever, while blood and Liver showed a dose response increase in E concentr
ation which correlated well with the different levels of E in the diet, the
central nervous system (Ch'S) followed the same pattern of increase of vit
amin E in brain tissue only when the diet was supplemented with 5, 30, or 6
0 mg E/kg diet. No further increase in E concentration was observed when th
e diet was supplemented with 250 or 500 mg E/kg diet. Similarly, the heart
tissue showed a significant increase in its E concentration when the was en
riched with 5, 30, or 60 mg E/kg diet, with no further increases at 250 or
500 mg. Vitamin C concentration in brain cortex and cerebellum plasma, live
r, and heart was reduced in the groups receiving 250 or 500 mg E/kg diet. C
ompared to the low E group, rats supplemented with the 60, 250 or 500 mg E/
kg diet showed a significant enhancement in striatal dopamine (DA) release,
but no differences were observed among the latter three groups. (C) 1999 E
lsevier Science B.V. All rights reserved.