Combination Of Alpha-tocopherol Research Articles

Effect of Prunus Dulcis & Álpha-Tocopherol in Ethanol Induced Dyslipidemia In Wistar Rats

The study is aimed at assessing the effect of Prunus dulcis and alpha-tocopherol treatment against ethanol induced dyslipidemia in Wistar rats. 30 albino Wistar rats were selected based on the selection criteria and equally distributed into 5 groups – Control, ethanol, Prunus dulcis, alpha-tocopherol and combination of alpha-tocopherol + Prunus dulcis treated for 40 days. After the treatment for 40 days, all the animals were euthanized and a retro-orbital puncture was made to collect the blood samples for biochemical investigations. Obtained results were statistically analysed using ANOVA. Compared to ethanol group alpha tocopherol, Prunus dulcis and alpha tocopherol + Prunus dulcis treatment significantly decreased total cholesterol and triglycerides levels with p value <0.001. High density lipoprotein (66.31%) levels in the ethanol group were decreased compared to the control group and were significantly increased in other groups. Low density lipoprotein and Very low density lipoprotein levels were higher in the ethanol group compared with the control group and were significantly reduced in other groups with p value <0.001. Results suggest that ethanol has an ill effect on the lipid profile. Treatment with Prunus dulcius and alpha-tocopherol both solely or in combination has produced beneficial effects against dyslipidemia.

Alpha-Tocopherol Surface Coating improves shelf life ofThompson Seedless grapes

The search for biodegradable, non-toxic, healthy and eco-friendly treatments to increase the shelf life of fruits results in the use of edible, biodegradable films, or surface coatings. Under tropical conditions prevailing high temperatures coupled with low humidity severely affect the grape quality and reduce shelf life. Guar gum (0.25 %) with different levels of alpha tocopherols viz.; 0.2, 0.4 and 0.6 percent were applied on bunches of Thompson Seedless with objective to improve quality for extended shelf life. Treated bunches of Thompson Seedless were placed at 10℃ and 60-65 percent RH for 28 days. Observations showed that the application of guargum with alpha-tocopherol improved overall appearance, delayed pattern of TSS and acidity changes, increased antioxidant activities and total phenol content. A combination of alpha-tocopherol (0.6 %) with guar gum (0.25%) was found more effective over other combinations.

Synergistic and antagonistic effects between alpha-tocopherol and phenolic acids in liposome system: spectroscopic study

The physicochemical interactions between alpha-tocopherol and three phenolic acids, which constitute main phenolics in coffee brew: caffeic, chlorogenic and ferulic acid, in l-α-phosphatidylcholine liposome system were studied. Steady-state and fluorescence lifetime measurements were applied to elucidate location of investigated phenolic acids in liposomes, and the results have shown that ferulic acid is most embedded into membrane structure. Lipophilic studies have shown that at pH 7.4 the partition coefficients for all phenolic acids are similar. Antioxidant capacity measurements of studied antioxidants were taken using fluorescent probe BODIPY. The synergistic effect was observed in all tested antioxidant systems with the exception of sample consisting of chlorogenic acid (2.5 μM) and alpha-tocopherol (2.5 μM), where antagonistic effect was noted. Concentration of antioxidants was a significant factor in the observed phenomenon. The most effective antioxidant system against oxidation in liposomes was combination of alpha-tocopherol and ferulic acid. This phenomenon could be explained by interaction of ferulic acid with the interior of the phospholipids membrane.

Oxidative stress in rat striatum after pilocarpine-induced seizures is diminished by alpha-tocopherol

Alpha-tocopherol has numerous nonenzymatic actions and is a powerful liposoluble antioxidant. The objective of the present study was to evaluate the neuroprotective effects of alpha-tocopherol in rats against oxidative stress caused by pilocarpine-induced seizures. Wistar rats were intraperitoneally treated with 0.9% saline (control group), alpha-tocopherol (200mg/kg, alpha-tocopherol group), pilocarpine (400mg/kg, pilocarpine group), or the combination of alpha-tocopherol (200mg/kg) and pilocarpine (400mg/kg, i.p.; alpha-tocopherol plus pilocarpine group). After the treatments, all groups were observed for 24h. The superoxide dismutase (Mn-SOD) and catalase activities, lipid peroxidation and nitrite concentrations were measured using spectrophotometrically methods. To clarify the mechanism of alpha-tocopherol on oxidative stress in pilocarpine model, Western blot analysis of Mn-SOD and catalase in rat striatum were performed. In the pilocarpine group, rats showed a significant increase in lipid peroxidation and nitrite levels. However, there were no alterations on Mn-SOD activity. On the other hand, the catalase activity augmented in pilocarpine group. In the alpha-tocopherol and pilocarpine co-administered rats, antioxidant treatment significantly reduced the lipid peroxidation level and nitrite content and increased the Mn-SOD and catalase activities in rat striatum after seizures. Pilocarpine, alpha-tocopherol plus pilocarpine and alpha-tocopherol groups did not affect of the Mn-SOD and catalase mRNA or protein levels. Our findings strongly support the hypothesis that oxidative stress occurs in striatum during pilocarpine-induced seizures, indicating that brain damage induced by the oxidative process plays a crucial role in seizures pathogenic consequences, which implies that strong protective effect could be achieved using alpha-tocopherol.

A combination of alpha-tocopherol, vitamin C and N-acetyl cysteine increases unsaturated fatty acid levels in hydrogen peroxide-induced Candida tropicalis (ATCC 13803).

This research was aimed at evaluating the antioxidant effects of combinations of alpha lipoic acid (LA), vitamin C (VC), N-acetyl cysteine (NAC) and alpha-tocopherol (TOC) on lipid level and fatty acid composition of C. tropicalis (ATCC 13803) against hydrogen peroxide toxicity. According to the experimental results, the cell density of C. tropicalis increased significantly in NAC+LA+H2O2, NAC+TOC+ H2O2 and NAC+VC+H2O2 groups (p<0.001) at the end of 48 and 72 h incubation times. The total lipid level in H2O2 and H2O2 + antioxidant-supplemented groups was lower than that of the control group. In the fatty acid composition of C. tropicalis, the palmitic acid level was raised in the NAC group (p<0.05), whereas its level was reduced in the other supplemented groups. While the oleic acid level increased in NAC+TOC+H2O2 and NAC+VC+H2O2 (p<0.001) groups, its level slightly decreased in the H2O2 group. The linolenic acid level was low in all the supplemented groups, but linoleic acid and total mono-unsaturated fatty acid (MUFA) levels were high in these groups compared with the control group. Total polyunsaturated fatty acid level (PUFA) decreased in NAC and H2O2 groups (p<0.01), but its level increased in NAC+LA+H2O2 and NAC+TOC+H2O2 groups (respectively, p<0.01, p<0.001). Total saturated fatty acid level decreased significantly in NAC+TOC+H2O2, NAC+H2O2 and NAC+VC+H2O2 (p<0.001) groups (p<0.01), whereas total unsaturated fatty acid level increased in NAC, NAC+H2O2, NAC+LA+H2O2, NAC+TOC+H2O2 and NAC+VC+H2O2 groups. In conclusion, our data showed that the levels of total unsaturated fatty acid, MUFA and PUFA were raised with the combinations of NAC and TOC, LA and VC in C. tropicalis cells subjected to hydrogen peroxide toxicity.

Nonenzymatic antioxidant activity of four organosulfur compounds derived from garlic.

The nonenzymatic antioxidant activity of diallyl sulfide (DAS), diallyl disulfide (DADS), S-ethyl cysteine (SEC), and N-acetyl cysteine (NAC) in the liposome system was examined. The antioxidant protection from these organosulfur agents was concentration dependent (p < 0.05). SEC and NAC showed significantly lower lipophilicity and greater reducing power than DAS and DADS (p < 0.05). Greater antioxidant protection was presented in the combinations of alpha-tocopherol with four organosulfur agents than alpha-tocopherol treatment alone (p < 0.05), and SEC and NAC showed greater sparing effects on alpha-tocopherol (p < 0.05). Four organosulfur agents lost antioxidant activity when the temperature was 65 degrees C (p < 0.05). At pH 2.5 and 10, DAS and DADS still showed antioxidant activity (p < 0.05). On the basis of the observed nonenzymatic antioxidant protection, these organosulfur compounds are potent agents for enhancing lipid stability.

Individual and combined antioxidant effects of seven phenolic agents in human erythrocyte membrane ghosts and phosphatidylcholine liposome systems: importance of the partition coefficient.

Antioxidant activities of seven phenolic agents against Fe(2+)-induced lipid oxidation were compared with alpha-tocopherol, beta-carotene, and vitamin C in human erythrocyte membrane ghosts and liposome systems. The antioxidant activity of five test flavonoids followed the order catechin > epicatechin > rutin > quercetin > myricetin in both systems (p < 0.05), which was negatively correlated with their partition coefficients. The antioxidant interaction of these phenolic agents with alpha-tocopherol, beta-carotene, or vitamin C in inhibiting Fe(2+)-induced lipid oxidation was examined. Synergistic effects were present in the combinations of alpha-tocopherol plus caffeic acid, catechin, or epicatechin as well as in all combinations of vitamin C plus phenolic antioxidants. On the basis of the stronger individual and combined effects present in caffeic acid, catechin, and epicatechin, the application of these three phenolic agents with or without alpha-tocopherol, beta-carotene, and vitamin C may provide stronger protective benefits against lipid oxidation, which may be helpful for oxidation-related diseases prevention.

Randomised trial of α-tocopherol and β-carotene supplements on incidence of major coronary events in men with previous myocardial infarction

Epidemiological data suggest that the intake of antioxidants such as alpha-tocopherol (vitamin E) and beta-carotene has an inverse correlation with the incidence of coronary heart disease. The results from clinical trials of antioxidant supplementation in people with known coronary heart disease are inconclusive. We studied the frequency of major coronary events in 1862 men enrolled in the alpha-tocopherol beta-carotene Cancer Prevention Study (smokers aged between 50 and 69 years) who had a previous myocardial infarction. In this randomised, double-blind. placebo-controlled study, men had received dietary supplements of alpha-tocopherol (50 mg/day), beta-carotene (20 mg/day), both, or placebo. The median follow-up was 5.3 years. The endpoint of this substudy was the first major coronary event after randomisation. Analyses were by intention to treat. 424 major coronary events (non-fatal myocardial infarction and fatal coronary heart disease) occurred during follow-up. There were no significant differences in the number of major coronary events between any supplementation group and the placebo group (alpha-tocopherol 94/466; beta-carotene 113/461; alpha-tocopherol and beta-carotene 123/497; placebo 94/438 [log-rank test, p = 0.25]). There were significantly more deaths from fatal coronary heart disease in the beta-carotene (74/461, multivariate-adjusted relative risk 1.75 [95% CI 1.16-2.64], p = 0.007) and combined alpha-tocopherol and beta-carotene groups (67/497, relative risk 1.58 [1.05-2.40], p = 0.03) than in the placebo group (39/438), but there was no significant increase in the alpha-tocopherol supplementation group (54/466, relative risk 1.33 [0.86-2.05], p = 0.20). The proportion of major coronary events in men with a previous myocardial infarction who smoke was not decreased with either alpha-tocopherol or beta-carotene supplements. In fact, the risk of fatal coronary heart disease increased in the groups that received either beta-carotene or the combination of alpha-tocopherol and beta-carotene; there was a non-significant trend of increased deaths in the alpha-tocopherol group. We do not recommend the use of alpha-tocopherol or beta-carotene supplements in this group of patients.

Effects of methylprednisolone and the combination of alpha-tocopherol and selenium on arachidonic acid metabolism and lipid peroxidation in traumatized spinal cord tissue.

Traumatic injury of the spinal cord leads to a series of pathological events that result in tissue necrosis and paralysis. Among the earliest biochemical reactions are hydrolysis of fatty acids from membrane phospholipids, production of biologically active eicosanoids, and peroxidation of lipids. This study examines the effect of agents purported to improve recovery following spinal cord trauma, methylprednisolone sodium succinate (MPSS) and the combination of alpha-tocopherol and selenium (Se), on the posttraumatic alterations of membrane lipid metabolism. Pretreatment with either MPSS or alpha-tocopherol and Se reduced the trauma-induced release of total FFA including arachidonate in the injured spinal cord tissue. In addition, these agents decreased the postinjury levels of prostanoids. Pretreatment with either MPSS or alpha-tocopherol and Se also completely prevented the trauma-induced loss of cholesterol while inhibiting the increase of a cholesterol peroxidation product, 25-hydroxycholesterol. These data suggest that: perturbation of membrane lipid metabolism may contribute to the tissue necrosis and functional deficit of spinal cord injury and MPSS or the combination of alpha-tocopherol and Se may protect injured spinal cord tissue, at least in part, by limiting these posttraumatic membrane lipid changes.