Antioxidant, carotene vitamin

Only one study to date has been conducted on the treatment of acute pancreatitis with antioxidants. Clemens et al. (1991) were unable to show any difference in the incidence or severity of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis in a prospective, randomized, double-blind, placebo-controlled trial of allopurinol. However, Salim (1991) performed a similar trial of the effect of allopurinol and DMSO in patients with pain from recurrent pancreatitis, and found significant benefit. On the basis that depletion of antioxidants is important in the pathogenesis of chronic pancreatitis, the administration of a cocktail of antioxidants was assessed for its effect on pain in this disease. Treatment with a combination of organic selenium, d-carotene, vitamins C and E, and methionine was of benefit in the initial pilot study, and in a placebo-controlled trial (San-dilands etal., 1990 Uden et al., 1990). 

The consumption of a mixture of phenolic compounds presented in apple or purple grape juice inhibited mammary carcinogenesis in 7,12-dimethylbenzo[a]anthracene (DMBA) treated rats (Liu and others 2005 Jung and others 2006). However, the individual antioxidants of these foods studied in clinical trials, including (3-carotene, vitamin C, and vitamin E, do not appear to have consistent preventive effects comparable to the observed health benefits of diets rich in fruits and vegetables, suggesting that natural phytochemicals in fresh fruits and vegetables could be more effective than a dietary supplement. 

The study of oxidative damage has sparked a debate about the role that antioxidants might play in illness and aging. Antioxidants are reducing agents. They donate electrons to substances that have been oxidized, decreasing the damage caused by free radicals. Dietary antioxidants include vitamins C and E, beta-carotene, and carotenoids. 

T Byers, G Perry. Dietary carotenes, vitamin C, and vitamin E as protective antioxidants in human cancers. Ann Rev Nutr 12 139-159, 1992. 

ACE drinks, containing beta-carotene (vitamin A precursor) and vitamins C and E. These materials are antioxidants and there is evidence that eliminating free radicals in the body will protect against cancer and cardiovascular diseases, particularly in older people. Suggested levels to... 

The lung also possesses nonenzymatic antioxidants such as vitamin E, beta-carotene, vitamin C, and uric acid. Vitamin E is lipid-soluble and partitions into lipid membranes, where it is positioned optimally for maximal antioxidant effectiveness. Vitamin E converts superoxide anion, hydroxyl radical, and lipid peroxyl radicals to less reactive oxygen metabolites. Beta-carotene also accumulates in cell membranes and is a metabolic precursor to vitamin A. Furthermore, it can scavenge superoxide anion and react directly with peroxyl-free radicals, thereby serving as an additional lipid-soluble antioxidant. Vitamin C is widely available in both extracellular and intracellular spaces where it can participate in redox reactions. Vitamin C can directly scavenge superoxide and hydroxyl radical. Uric acid formed by the catabolism of purines also has antioxidant properties and primarily scavenges hydroxyl radical and peroxyl radicals from lipid peroxidation. 

Nevertheless, at least six randomized, double-blind, placebo-controlled, intervention trials have assessed the effect of vitamin or micronutrient supplements on AMD risk. The consensus from these and other trials seems to suggest a positive response of the retina as well as improved visual performance from vitamin and mineral supplementation such as the AREDS formulation (see above). Specifically, the AREDS results should be interpreted as understanding that the formulation was effective in slowing the risk of progression of AMD in persons 55 years of age and older who had some macular changes consistent with early age-related maculopathy. More recently, substantiation of these results was reported on a primarily white population as part of the Rotterdam Study. An above-median intake of beta-carotene, vitamin C, vitamin E, and zinc was associated with a 35% reduced risk of AMD. Still other clinical research has demonstrated shortterm beneficial effects in small populations for lutein and a combination of lutein and antioxidants in AMD. 

The lipidic vitamins (ref.84) include vitamin A (32), a substance intrinsic to the physiology of vision, vitamin E (83), a natural protective antioxidant, and vitamins K, (84) with Kj (85), antihemorrhagic compounds, each of which is derivable from an initial natural product intermediate. Although traditionally a -ionone obtained from citral (a major constituent of lemon grass oil) was used for the synthesis of vitamin A, a synthetic source has now replaced this in a process which also gives /g-carotene. In one method the Cl4 aldehyde in that process is reacted with a C6 eneyne component and selective hydrogenation followed by dehydration and isomerisation affords the final product (ref.85). 

Well-known naturally occurring antioxidants are vitamin C (ascorbic acid), which are contained in many citrus fruits, or on the other hand manbers of vitamin E family, which appear for example in nnts and snnflower seeds. Also P-carotene and lycopine, which also belong to the family of caro-tenoides, are further examples of natural antioxidants. On the other hand, there are many synthetic... 

The Supplementation Vitamin, Minerals and Antioxidant Trial (SU. VI.M.AX) is testing, in 15,000 healthy French men and women, whether a combination of antioxidant vitamins and minerals, including vitamin E, p-carotene, vitamin C, selenium, and zinc, protects against CHD. In the United States, an intervention trial was started with 8000 women with recent CHD in order to test in a factorial design the effect of P-carotene, vitamin E, and vitamin C. 

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