Effect of Dietary Vitamin E Supplementation on Liver Oxidative Damage in Rats with Water-Immersion Restraint Stress

Vitamin E reduces oxidative stress in brains of male albino male rats undergoing immobilization

Stress can lead to various health problems. Exposure to stress is linked to several diseases including cancer, hypertension, diabetes, mental disorders, and heart attacks. Stress stimulates several pathways that produce free radicals, which increases oxidative stress. This results in functional and structural damage to organs, such as the brain, which is highly sensitive to oxidative stress Vitamin E is a naturally occurring potent antioxidant used for various purposes. The main purpose of the current study was to evaluate how vitamin E protects the brain and to what extent it affects antioxidant levels in rats subjected to two hours per day of immobilization stress, the form of stress with the strongest effect. The rats were immobilized by folding their limbs in and wrapping them in netting to prevent movement, while allowing their tails to be extended. The rats were then hung upside down. The effect of vitamin E was tested by intraperitoneally injecting rats with 40 mg/kg of vitamin E daily. Oxidative stress parameters were determined at the completion of the experiment. A dramatic decrease in malondialdehyde (MDA) levels and an increase in catalase (CAT), including glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), has been shown by vitamin E in the brain. The effects of vitamin E were significantly higher in the acute and chronic stress groups than in the control group. Vitamin E can decrease oxidative stress in stressed rats, indicating that it exerts therapeutic and protective effects owing to its antioxidant properties.

Quantification of Tocopherols, Tocotrienols and γ-Oryzanol Contents of Local Rice Varieties in Northeastern Thailand

A total of 101 local rice varieties, composted of 85 glutinous and 16 non-glutinous varieties grown in wet season 2016, were analyzed for tocopherols (TOC), tocotrienols (T3) and γ-oryzanol (Orz). Two popular varieties, RD6 and KDML105, were used as standard checks for glutinous and non-glutinous varieties, respectively. γ-TOC was found in all glutinous varieties (0.47-9.78 mg/kg), which were higher than RD6 (0.16 mg/kg). α-TOC was found in 40 varieties (1.02-6.29 mg/kg), only 6 varities were higher than RD6 (3.95 mg/kg). δ-T3 was found in 81 varieties (0.57-7.00 mg/kg), mostly varities were higher than RD6 (0.67 mg/kg). γ-T3 was found in all glutinous varieties (8.00-22.1 mg/kg), while RD6 contained 13.3 mg/kg. For α-T3, it was found in 39 glutinous varieties (1.52-9.94 mg/kg), mostly varities were higher than RD6 (2.62 mg/kg). Orz was found in all glutinous rice varieties (276-638 mg/kg), while RD6 contained 423 mg/kg. γ-TOC was found in all non-glutinous varieties (0.67-5.21 mg/kg), which were higher than KDML105. α-TOC was found in only 5 varieties (1.92-2.83 mg/kg), while KDML105 contained 2.23 mg/kg. δ-T3 was found in all non-glutinous varieties (1.64-8.87 mg/kg), which were higher than KDML105 (0.71 mg/kg). γ-T3 was also found in all non-glutinous varieties (8.80-17.58 mg/kg), while KDML105 contained 15.8 mg/kg. α-T3 was found in 9 non-glutinous varieties (4.56-8.93 mg/kg),while KDML105 contained only 0.86 mg/kg. Orz was also found in all those non-glutinous varieties (272-469 mg/kg), while KDML105 contained 469 mg/kg. These results indicate that γ-T3 was the highest vitamin E isomer present in all rice samples, while γ-TOC, α-TOC, δ-T3 and α-T3 were present in trace amounts. Orz was found in all local rice varieties.

α-Tocopherol Protects the Heart, Muscles, and Testes from Lipid Peroxidation in Growing Male Rats Subjected to Physical Efforts

The effect of α-tocopherol supplementation on adaptation to training is still equivocal. The aim of the study was to determine the effect of training and α-tocopherol supplementation on α-tocopherol and thiobarbituric acid reactive substance (TBARS) concentration in the rat liver, heart, muscles, and testes. Male Wistar rats (n = 32) were divided into four groups (nonsupplemented, not trained—C; nonsupplemented, trained—CT; supplemented, not trained—E; supplemented and trained—ET). During the 14-day experimental period, 2 mg/d of vitamin E as α-tocopherol acetate was administered to the animals (groups E and ET). Rats in the training group (CT and ET) were subjected to 15 minutes of treadmill running each day. The α-tocopherol levels in rat tissues were assessed using high-performance liquid chromatography (HPLC). Lipid peroxides were determined by TBARS spectrophotometric method. α-Tocopherol had a significant impact on α-tocopherol concentration in all tissues. Training increased the α-tocopherol concentration in the heart and muscles but reduced it in the liver. Training also caused increased lipid peroxidation in the muscles, heart, and testes; but a higher α-tocopherol content in tissues reduced the TBARS level. The main finding of the study is that impaired α-tocopherol status and its adequate intake is needed to maintain optimal status to prevent damage to the skeletal and cardiac muscles as well as the testes in growing individuals.

The reduced bactericidal activity of neutrophils as an incisive indicator of water-immersion restraint stress and impaired exercise performance in mice

The incisive evaluation of psychological stress may be required to determine the exercise performance of stressed hosts. We investigated objective markers of psychological stress that reflect exercise performance, focusing on the neutrophil function. We used murine water-immersion restraint (WIR) stress for our assessments. After receiving WIR for 1 or 2 h, mice were exercised on an airtight treadmill that monitors their respiratory exchange ratio. The neutrophil function was analyzed after WIR stress. Although the control mice (without WIR) showed good combustion of both carbohydrates and lipids as energy sources during treadmill exercise, mice that underwent 2-h WIR did not combust carbohydrates or lipids effectively, drastically reducing their performance. In contrast, the 1-h WIR mice showed carbohydrate combustion (albeit a slow response) but did not use lipids for energy, thereby running longer than the 2-h WIR mice but shorter than the control mice. The bactericidal activity of neutrophils, but not their superoxide production or microsphere-phagocytic activity, was significantly reduced by 1-h WIR and further reduced by 2-h WIR, indicating a significant association between WIR stress and exercise performance. The neutrophil bactericidal activity may be a good indicator of psychological stress and a useful tool for precisely assessing exercise performance.

Role of Borage Seed Oil and Fish Oil with or without Turmeric and Alpha- Tocopherol in Prevention of Cardiovascular Disease and Fatty Liver in Rats

The aim of the present research was to Study the prevention of dyslipidemia, oxidative stress, inflammation and fatty liver as risk factors for cardiovascular disease via intervention by borage oil (B) and fish oil (F) with or without turmeric (T) and alpha-tocopherols (TC). Fatty acids were assessed in both oils while curcuminoids were determined in turmeric. Rats were divided into; first group fed on balanced diet and designated as normal control (NC), second fed on dyslipidemic and steatohepatitis (DS) inducer diet which represented the DS control group and groups 3-6 fed on DS inducer diet with daily oral administration of B, B+T+TC, F and F+T+TC; respectively for 5 weeks. Liver fat and plasma lipid profile, oxidative stress and inflammatory biomarker and liver and heart histopathology were assessed. Results showed gamma linolenic to be 21.01% in B. F contained eicosapentaenoic as 22.768% and docosahexaenoic acid as 13.574%.Total curcuminoids were 4.63 mg/g turmeric. The DS control group showed significant dyslipidemia, elevated malondialdehyde (MDA), tumor necrosis factor-alpha and liver fat with significant reduction in total antioxidant capacity (TAC) compared to NC. The different treatments produced significant improvement in all the parameters and histopathology. F was superior to B in ameliorating liver histopathological changes while B was more efficient in elevating TAC. B was more promising in improving lipid profile and liver fat compared to B + T + TC, while the latter was superior in improving MDA and liver histopathology. Fish oil was more efficient than F+TC+T except for TAC and high density lipoprotein cholesterol which were more improved on addition of TC and T. Conclusion: Borage and fish oil with or without antioxidants protect from cardiovascular and fatty liver diseases with variable degrees.

Biologic Stress, Oxidative Stress, and Resistance to Drugs: What Is Hidden Behind

Stress can be defined as the homeostatic, nonspecific defensive response of the organism to challenges. It is expressed by morphological, biochemical, and functional changes. In this review, we present biological and oxidative stress, as well as their interrelation. In addition to the mediation in biologic stress (central nervous, immune, and hormonal systems) and oxidative stress, the effect of these phenomena on xenobiotic metabolism and drug response is also examined. It is concluded that stress decreases drug response, a result which seems to be mainly attributed to the induction of hepatic drug metabolizing enzymes. A number of mechanisms are presented. Structure-activity studies are also discussed. Vitamin E, as well as two synthetic novel compounds, seem to reduce both oxidative and biological stress and, consequently, influence drug response and metabolism.