Possible Interaction: Vitamin E and Caffeic Acid

“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.”

“Pretreatment of the cells with alpha-tocopherol significantly increased the resistancy against the cytotoxic action of UV irradiation and antioxidants such as sodium ascorbate, gallic acid, n-propyl gallate and caffeic acid.”

“Quercetin, rutin, (+)-catechin, caffeic acid , and chlorogenic acid proved to be better inhibitors than alpha-tocopherol and ascorbic acid.”

“ Caffeic acid also increased vitamin E levels in plasma (2.74 micromol/L to 4.09 micromol/L for normal diet; p < 0.001; 2.78 micromol/L to 4.94 micromol/L for iron supplemented diet p < 0.001).”

“DOPAC and CA at concentration 50 μM suppressed α-TOH consumption during oxidation of soybean phosphatidylcholine (2.8 mM) multilamellar vesicles containing 15 μM α-TOH, in which the lipophilic initiator 2,2′-azobis (2,4-dimethylvaleronitrile) (6 mM) was incorporated.”

“DOPAC and CA suppressed the α-TOH consumption in a dose-dependent manner.”

“Dietary supplementation of caffeic acid (0.2 and 0.8% w/w) in rats resulted in a statistically significant increase of alpha-tocopherol both in plasma and lipoprotein.”

“This formation of caffeic acid was proposed to be responsible for the synergistic activity of R0 and α-tocopherol since the formation of an additional antioxidant could further increase the oxidative stability of the emulsion.”

“In LDL enriched with alpha-tocopherol, caffeic acid induces an inhibition period of oxidation longer than that expected from the sum of discrete periods characteristic of the phenolic acid and alpha-tocopherol.”

“Results suggest that caffeic acid acts synergistically with alpha-tocopherol , extending the antioxidant capacity of LDL by recycling alpha-tocopherol from the alpha-tocopherol radical (i.e., alpha-tocopheroxyl radical).”

“… alpha-tocopherol depletion , subsequent heavy … by caffeic and p-coumaric acids, i.e., phenolic acids present in foods and beverages, by a mechanism involving the one-electron transfer … and the ferrylmyoglobin, with formation of metmyoglobin and the corresponding phenoxyl radicals from caffeic and p-coumaric acids, as previously discussed.”