Little is known about the effect of vitamin E on brain function. Therefore, in this study we evaluated the effect of tocotrienol rich fraction (TRF) on behavioral impairment and oxidative stress in aged rats. Thirty-six male Wistar rats (young: 3-months-old; aged: 21-months-old) were treated with either the control (olive oil) or TRF (200 mg/kg) for 3 months. Behavioral studies were performed using the open field test and Morris water maze (MWM) task. Blood was taken for assessment of DNA damage, plasma malondialdehyde (MDA) and vitamin E, and erythrocyte antioxidant enzyme activity. Brains were also collected to measure vitamin E levels. Results showed that aged rats exhibited reduced exploratory activity, enhanced anxiety and decreased spatial learning and memory compared with young rats. DNA damage and plasma MDA were increased, and vitamin E levels in plasma and brain were reduced in aged rats. Aged rats supplemented with TRF showed a markedly reduced level of anxiety, improved spatial learning and memory, reduced amount and severity of DNA damage, a reduced level of MDA, and increased levels of antioxidant enzyme activity and plasma/brain vitamin E compared with age-matched controls. In conclusion, TRF supplementation reverses spatial learning and memory decline and decreases oxidative stress in aged rats.
Rice (Oryza sativa) is the most important staple food for a large part of the world’s human population, especially in East and South Asia, the Middle East, Latin America, and the West Indies. It provides more than one fifth of the calories consumed worldwide by the human. It is the second leading cereal crop and staple food of half of the world’s population. It is grown in at least 114 countries with global production of 645 million tons; share of Asian farmers is about 90% of the total produce. Rice bran, brown outer layer of rice kernel, is mainly composed of pericarp, aleurone, subaleurone layer, and germ. It contains appreciable quantities of nutrients like protein, fat, and dietary fiber. Furthermore, it contains substantial amount of minerals like K, Ca, Mg, and Fe. Presence of antioxidants like tocopherols, tocotrienols, and γ-oryzanol also brighten prospects of rice bran utilization for humans as functional ingredient to mitigate the life-threatening disorders. Moreover, in the developing countries, budding dilemma of food crisis, arising due to lower crop yields and escalating population, needs to utilize each pent of available resources. To provide enough food to all people, there is the holistic approach of using the by-products generated during food processing and preparations. Rice is being processed in well-established industry, but the major apprehension is the utilization of its by-products; rice bran (5-8%) and polishing (2-3%) that are going as waste. Rice processing or milling produces several streams of materials including milled rice, bran, and husk. In developing countries, rice bran is considered as a by-product of the milling process and commonly used in animal feed or discarded as a waste. The potential of producing rice bran at the global level is 29.3 million tons annually, whereas the share of Pakistan is worked out to be 0.5 million tons. In present paper, attempt has been made to highlight the significance of these valuable but neglected ingredients under various headings.
Skeletal muscle satellite cells are heavily involved in the regeneration of skeletal muscle in response to the aging-related deterioration of the skeletal muscle mass, strength, and regenerative capacity, termed as sarcopenia. This study focused on the effect of tocotrienol rich fraction (TRF) on regenerative capacity of myoblasts in stress-induced premature senescence (SIPS). The myoblasts was grouped as young control, SIPS-induced, TRF control, TRF pretreatment, and TRF posttreatment. Optimum dose of TRF, morphological observation, activity of senescence-associated β -galactosidase (SA- β -galactosidase), and cell proliferation were determined. 50 μ g/mL TRF treatment exhibited the highest cell proliferation capacity. SIPS-induced myoblasts exhibit large flattened cells and prominent intermediate filaments (senescent-like morphology). The activity of SA- β -galactosidase was significantly increased, but the proliferation capacity was significantly reduced as compared to young control. The activity of SA- β -galactosidase was significantly reduced and cell proliferation was significantly increased in the posttreatment group whereas there was no significant difference in SA- β -galactosidase activity and proliferation capacity of pretreatment group as compared to SIPS-induced myoblasts. Based on the data, we hypothesized that TRF may reverse the myoblasts aging through replenishing the regenerative capacity of the cells. However, further investigation on the mechanism of TRF in reversing the myoblast aging is needed.
The effect of γ -tocotrienol, a vitamin E isomer, in modulating gene expression in cellular aging of human diploid fibroblasts was studied. Senescent cells at passage 30 were incubated with 70 μ M of γ -tocotrienol for 24 h. Gene expression patterns were evaluated using Sentrix HumanRef-8 Expression BeadChip from Illumina, analysed using GeneSpring GX10 software, and validated using quantitative RT-PCR. A total of 100 genes were differentially expressed (P < 0.001) by at least 1.5 fold in response to γ -tocotrienol treatment. Amongst the genes were IRAK3, SelS, HSPA5, HERPUD1, DNAJB9, SEPR1, C18orf55, ARF4, RINT1, NXT1, CADPS2, COG6, and GLRX5. Significant gene list was further analysed by Gene Set Enrichment Analysis (GSEA), and the Normalized Enrichment Score (NES) showed that biological processes such as inflammation, protein transport, apoptosis, and cell redox homeostasis were modulated in senescent fibroblasts treated with γ -tocotrienol. These findings revealed that γ -tocotrienol may prevent cellular aging of human diploid fibroblasts by modulating gene expression.
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