RESUMEN
The objective of the present study was to investigate age-related differences in erythrocyte membrane fluidity (EMF) and changes in antioxidant capacity following supplementation. A total of seventy-four children were randomly divided into two groups: group A1 was the placebo-controlled group and group A2 was supplemented daily with 600 µg retinol, 1·0 mg ß-carotene, 100 mg tocopherol, 300 mg ascorbic acid and 200 µg Se. A total of ninety young people were randomly divided into B1 and B2 groups, and ninety-one elderly subjects were divided into C1 and C2 groups. Groups B1 and C1 were placebo-controlled groups, and groups B2 and C2 were daily supplemented with 900 µg retinol, 1·5 mg ß-carotene, 200 mg tocopherol, 500 mg ascorbic acid and 400 µg Se. Results showed that plasma malondialdehyde (MDA) was 5·35 µmol/l in children, which was lower than in young and elderly people. The MDA levels of the young and elderly individuals in the treated groups were significantly lower compared with the control groups, but the supplementation did not alter MDA levels in children. At baseline, there was a lower value of polarisation (ρ) and microviscosity (η) in children, indicating a higher EMF, than in both the young and elderly subjects. After the 2-month trial, the ρ and η values of young and elderly subjects in the treated groups decreased significantly in comparison with the placebo groups, indicating an increase in EMF. In conclusion, there was a background of higher MDA levels and lower EMF in young and elderly people than in children, which could be improved by antioxidant supplementation.
Asunto(s)
Antioxidantes/administración & dosificación , Suplementos Dietéticos , Membrana Eritrocítica/efectos de los fármacos , Fluidez de la Membrana/efectos de los fármacos , Micronutrientes/administración & dosificación , Población Rural , Adulto , Anciano , Antioxidantes/farmacología , Niño , Humanos , Malondialdehído/metabolismo , Micronutrientes/farmacologíaRESUMEN
OBJECTIVE: To examine the effect of multiple micronutrients supplementation on anti-oxidative activity and decreasing oxidized DNA damage of lymphocytes in Chinese children. METHODS: 82 healthy children in a rural areas, aged 9-11 years, were selected and randomized allocated into group receiving supplements and control group with each of them 41. 24-hour dietary recall was used to collect data on daily nutrient intakes of the research subjects. The subjects in the supplement group were given vitamin A (VA) 600 microg, beta-carotene (beta-C) 1.0 mg, vitamin E (VE) 100 mg, vitamin C (VC) 300 mg and Na2SeO3(Se) 200 microg in a tablet on daily base while those in the control group took a same-sized color placebo tablet. The trial lasted 8 weeks. 5 ml blood samples from each subject were taken during 7 to 9 o'clock in the morning. DNA damage of lymphocytes and levels of plasma VA, VE, VC, beta-C, Se, malondialdehyde (MDA), activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were then analyzed twice before and after the 8-week of trial. RESULTS: The low intakes of VA, VC and Se only accounted for 50.6%, 65.6% and 67.3% of their recommended nutrient intake (RNI) respectively. After the trial, levels of plasma beta-C, VA, VE, VC and Se in the supplemented group increased by 13.4%, 32.8%, 11.5%, 46.9% and 24.6% respectively, compared with the control group, indicating that nutritional status regarding antioxidant nutrients had largely been improved. GSH-Px activity had a significant increase in the supplement group than before the supplement and in the control group (P < 0.01). GSH-Px before the trial (the 100.4 U/ml) also showed significant increase after the trial (161.7 U/ml) (P < 0.01). However, the values of SOD and MDA significantly decreased after the trial. Analysis of DNA damage indicated that there was no significant difference in the intrinsic damage of DNA (P > 0.05). Significant decreases of oxidized DNA damage induced by 5 micromol/L, 10 micromol/L and 25 micromol/L H2O2 were found more in peripheral lymphocytes of the supplemented group, than in pre-supplement and the control group after the trial (P < 0.01). CONCLUSION: Supplementation of multiple micronutrients could effectively increase the levels of beta-C, VA, VE, VC and Se in plasma, and GSH-Px activity. In the meantime, MDA and oxidized DNA damage induced by a low level H2O2 decreased significantly after the trial. The reason accounted for the decrease of SOD activity after the trial needs to be further studied.