Effect of vitamin E intake on levels of vitamins E and C in the central nervous system and peripheral tissues: implications for health recommendations.
Vitamin E (alpha-gamma-tocopherol) is an important component in biological membranes. A decrease in its concentration imposes structural and functional 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 regions of the brain, and its influence on vitamin C levels and neurological function. 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. However, while blood and liver showed a dose response increase in E concentration which correlated well with the different levels of E in the diet, the central nervous system (CNS) followed the same pattern of increase of vitamin E in brain tissue only when the diet was supplemented with 5, 30, or 60 mg E/kg diet. No further increase in E concentration was observed when the 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 enriched 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, liver, and heart was reduced in the groups receiving 250 or 500 mg E/kg diet. Compared 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.
Martin
A
A
USDA-Neuroscience Laboratory, Jean Mayer USDA Human Nutrition, Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA. martina_ne@hrmc.tufts.edu
Janigian
D
D
Shukitt-Hale
B
B
Prior
R L
RL
Joseph
J A
JA
D000818:Animals; D001205:Ascorbic Acid / Q000032:analysis* / Q000097:blood; D001835:Body Weight; D001923:Brain Chemistry / Q000187:drug effects*; D002531:Cerebellum / Q000737:chemistry / Q000187:drug effects; D002540:Cerebral Cortex / Q000737:chemistry / Q000187:drug effects; D004435:Eating; D006321:Heart / Q000187:drug effects; D006624:Hippocampus / Q000737:chemistry / Q000187:drug effects; D008099:Liver / Q000737:chemistry / Q000187:drug effects; D008297:Male; D009206:Myocardium / Q000737:chemistry; D018673:Nutrition Policy; D051381:Rats; D011916:Rats, Inbred F344; D014810:Vitamin E / Q000032:analysis* / Q000097:blood / Q000494:pharmacology*
D014810:Vitamin E; D001205:Ascorbic Acid