The Effect Of Beta-Carotene Supplementation On Cellular Activities And DNA Damage In Young And Elderly People

Objectives To evaluate the effect of β-carotene(β-C) supplementation on celluar activities and DNA damage in young people ,and evaluate the effect of variable doses of β-carotene combined with vitamin E(VE) and vitamin C(VC) supplementation on cell's function and DNA damage in elderly people.Methods 192 young people (18-25y) were randomly divided into four groups: group 1: BC 16.70mg/d +VE5mg/d ; group 2: BC 8.35mg/d +VE5mg/d; group 3: BC 5.57mg/d +VE5mg/d; group 4: VE 5mg/d.The trial last 8 weeks. Moreover, 300 elderly people (60-75y) were randomly divided into five groups, group 1: BC16.70mg/d+VE200mg/d +VC300 mg/d ;group 2: BC 8.35mg/d+VE 200mg/d +VC300 mg/d; group3: BC 5.57mg/d+VE200mg/d +VC300 mg/d; group4: VE200mg/d +VC300 mg/d ;group 5: VE5mg/d .The trial last 16 weeks. The samples of blood and urine were collected at the beginning and the end of the trials.24h diet recall was used to evaluate young people's diet and nutrition status. H2O2-induced hemolytic degree of erythrocytewere measured before and after the supplementation.O6-MeG was analyzed by high performance capillary zone electrophoresis.The proliferation of lymphocytes was detected by the method of MTT.Results The intakes of vitamin A, E, C and seleium in young subjects were 87%, 89%, 75% and 111% of RNIs respectively.2 H2O2-induced hemolytic degree of erythrocyte in the second group of young subjects decreased significantly from 44.2% to 35.1% before and after the trial ( P<0.05) . But in elderly people, a significant decrease of hemolytic degree of erythrocyteafter the trial was found in group 1, 2 , 3 and 4 (P<0.01), compared with the trial. The lower levels of hemolytic degree of erythrocytewere in group 1,2,3 and 4 than one of the control (P<0.01).3 In young subjects, the activity of lymphocyte proliferation was significantly higher in group 1 (P<0.05) than that of group 4 after the trial (P<0.05). In elderly subjects, the activities of lymphocyte proliferation after the trial were significantly higher in group 1, 2, 3 and 4(P<0.05) than those before the trial. There were higher proliferation in group 1, 2, 3 and 4 than group 5 (P<0.01 or P<0.05 ); moreover, the proliferation of lymphocytes was higher in group 1 than group 4 (P<0.05).4 In young subjects, there were significant decreases of O6-MeG both in group 1 and group 2 after the trial, (P<0.01). In elderly subjects, significant decreases of O6-MeG were found in all four supplemented groups (P<0.01) after the trial (P<0.01). There were lower levels of O6-MeG in...