Possible Interaction: Methionine and Vitamin C

“Measurements were taken before and 4 h after administration of a placebo, oral methionine (L-methionine 0.1 g/kg) or oral methionine plus vitamin C (2 g) on 3 separate days.”

“Pretreatment with vitamins C and E prevented the effects of methionine on femoral and brachial arteries as well as on urinary 8-iso-prostaglandin F2α excretion.”

“Acute hyperhomocystinemia does not significantly alter arterial stiffness, as assessed by pulse wave analysis, whereas a combination of methionine and vitamin C leads to a similar reduction in augmentation index to that previously described after vitamin C alone.”

“Thiol reagents (tear side), including reduced glutathione 10−5 M ), blocked the effect of ascorbic acid (10−3 M) providing they were added to the bathing solution prior to the vitamin.”

“Addition of ascorbic acid enhanced amino acid absorption and this effect was maximum in case of methionine.”

“Apomorphine proved to be the most effective compound, fully antagonizing the effect of ascorbic acid at a concentration of 10 −6 M. A partial inhibition of the effect of ascorbic acid was induced by 10 −4 M serotonin, desipramine, imipramine and LSD.”

“Although ascorbic acid had a synergistic effect with methionine in stripped SBO, it showed a significant antagonistic effect in SBO.”

“Some (but not all) peptide sequences that contain one or more methionines instead of cysteine can significantly retard the oxidation of ascorbic acid but do not recycle it from dehydroascorbate into ascorbate.”

“ Methionine played an important role on the stability of ascorbic acid.”