RESUMEN
BACKGROUND: Vitamin E supplements containing tocotrienols are now being recommended for optimum health but its effects are scarcely known. The objective was to determine the effects of Tocotrienol Rich Fraction (TRF) supplementation on lipid profile and oxidative status in healthy older individuals at a dose of 160 mg/day for 6 months. METHODS: Sixty-two subjects were recruited from two age groups: 35-49 years (n = 31) and above 50 years (n = 31), and randomly assigned to receive either TRF or placebo capsules for six months. Blood samples were obtained at 0, 3rd and 6th months. RESULTS: HDL-cholesterol in the TRF-supplemented group was elevated after 6 months (p < 0.01). Protein carbonyl contents were markedly decreased (p < 0.001), whereas AGE levels were lowered in the > 50 year-old group (p < 0.05). Plasma levels of total vitamin E particularly tocopherols were significantly increased in the TRF-supplemented group after 3 months (p < 0.01). Plasma total tocotrienols were only increased in the > 50 year-old group after receiving 6 months of TRF supplementation. Changes in enzyme activities were only observed in the > 50 year-old group. SOD activity was decreased after 3 (p < 0.05) and 6 (p < 0.05) months of TRF supplementation whereas CAT activity was decreased after 3 (p < 0.01) and 6 (p < 0.05) months in the placebo group. GPx activity was increased at 6 months for both treatment and placebo groups (p < 0.05). CONCLUSION: The observed improvement of plasma cholesterol, AGE and antioxidant vitamin levels as well as the reduced protein damage may indicate a restoration of redox balance after TRF supplementation, particularly in individuals over 50 years of age.
RESUMEN
OBJECTIVE: The free radical theory of aging (FRTA) suggests that free radicals are the leading cause of deteriorating physiologic function during senescence. Free radicals attack cellular structures or molecules such as DNA resulting in various modifications to the DNA structures. Accumulation of unrepaired DNA contributes to a variety of disorders associated with the aging process. METHODS: A randomized, double-blinded placebo-controlled study was undertaken to evaluate the effect of Tri E Tocotrienol on DNA damage. Sixty four subjects 37-78 y old completed the study. A daily dose of 160 mg of Tri E Tocotrienol was given for 6 months. Blood samples were analyzed for DNA damage using comet assay, frequency of sister chromatid exchange (SCE), and chromosome 4 aberrations. RESULTS: Results showed a significant reduction in DNA damage as measured by comet assay after 3 mo (P < 0.01) and remained low at 6 mo (P < 0.01). The frequency of SCE was also reduced after 6 mo of supplementation (P < 0.05), albeit more markedly in the >50 y-old group (P < 0.01) whereas urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels were significantly reduced (P < 0.05). A strong positive correlation was observed between SCE with age, whereas weak positive correlations were observed in DNA damage and 8-OHdG, which were reduced with supplementation. However, no translocation or a stable insertion was observed in chromosome 4. CONCLUSION: Tri E Tocotrienol supplementation may be beneficial by reducing DNA damage as indicated by a reduction in DNA damage, SCE frequency, and urinary 8-OHdG.
