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Effects of flavonoid extract Enzogenol® with vitamin C on protein oxidation and DNA damage in older human subjects

Senthilmohan, Senti T., Zhang, Jingli, Stanley, Roger A.
Nutrition research 2003 v.23 no.9 pp. 1199-1210
DNA damage, Pinus radiata, ascorbic acid, bark, clinical trials, enzyme-linked immunosorbent assay, females, flavonoids, humans, males, mononuclear leukocytes, oxidation
In this study a 12 week clinical trial was conducted with Enzogenol®, a commercially available proanthocyanidin-rich flavonoid extract derived from the bark of Pinus radiata that was formulated with vitamin C. The study was to determine whether the oxidative injury markers of protein and DNA damage could be affected by the product. Twenty four (14 males and 10 females) subjects aged between 55-75 years completed the study. The group was given a twice daily dose of 240 mg of Enzogenol® and 120 mg vitamin C for 12 weeks and blood samples were collected at the start of the study before supplementation, 6 weeks and 12 weeks. Plasma samples were analysed for protein carbonyl concentrations as a measure of protein oxidation by an ELISA method. Isolated peripheral blood mononuclear cells were analysed for DNA damage using the alkaline comet assay. Protein carbonyl concentration reductions were highly significant after 6 and 12 weeks of supplementation. DNA damage reduction, as measured by the comet assay, was not significant after 6 weeks but highly significant after 12 weeks of supplementation.