Vitamin E supplementation protects erythrocyte membranes from oxidative stress in healthy Chinese middle-aged and elderly people.
Elderly people are subject to higher levels of oxidative stress than are young people. Vitamin E, as a powerful antioxidant residing mainly in biomembranes, may provide effective protection against oxidative membrane damage and resultant age-related deterioration, especially in the elderly. We hypothesized that appropriate levels of vitamin E supplementation would protect erythrocyte membranes from oxidative stress and thus improve membrane fluidity in healthy middle-aged and elderly people. To test this, we conducted a 4-month double-blind, randomized trial in which 180 healthy subjects (55-70 years old) were randomly divided into 4 groups: group C (control), and 3 treatment groups in which daily doses of 100 mg (VE1), 200 mg (VE2), and 300 mg (VE3) dl-α-tocopheryl acetate were administered. We measured plasma α-tocopherol concentration, malondialdehyde, and superoxide dismutase levels, erythrocyte hemolysis, and erythrocyte membrane fluidity at the beginning and end of the trial. After 4 months supplementation, plasma α-tocopherol concentrations in the 3 treatment groups had increased by 71%, 78%, and 95%, respectively (all P < .01), and significant decreases in plasma malondialdehyde concentrations were observed in these groups (all P < .05). Erythrocyte hemolysis was decreased by 20% to 38% after vitamin E supplementation (all P < .05), and in addition, groups VE2 and VE3 showed dramatic improvements in erythrocyte membrane fluidity (P < .01). Surprisingly, superoxide dismutase activity also decreased significantly in the treatment groups (all P < .05). In summary, vitamin E supplementation apparently alleviates oxidative stress in healthy middle-aged to elderly people, at least in part by improving erythrocyte membrane fluidity and reducing erythrocyte hemolysis.
The Institute of Human Nutrition, Medical College of Qingdao University, 38 Dengzhou Road, Qingdao, China.
Yongye
Y
Sun
Aiguo
A
Ma
Yong
Y
Li
Xiuxia
X
Han
Qiuzhen
Q
Wang
Hui
H
Liang
D000368:Aged; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism; D002681:China; D019587:Dietary Supplements; D004311:Double-Blind Method; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000097:blood*; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D012016:Reference Values; D013482:Superoxide Dismutase / Q000097:blood; D014810:Vitamin E / Q000097:blood / Q000494:pharmacology*; D024502:alpha-Tocopherol / Q000097:blood
D000975:Antioxidants; D014810:Vitamin E; D008315:Malondialdehyde; D013482:Superoxide Dismutase; D024502:alpha-Tocopherol