Possible Interaction: Tretinoin and Vitamin C

“We found that retinol/retinoic acid (vitamin A) and ascorbate ( vitamin C ) synergistically diminish DNA methylation levels and in doing so enhance the generation of naïve pluripotent stem cells.”

“The nature of these genes … the mechanism by which RA … AA act synergistically in inhibiting human breast cancer cell proliferation may involve the expression of genes that induce differentiation and … proliferation, and the up-regulation of antioxidant enzymes and proteins involved in apoptosis, cell cycle regulation and DNA repair.”

“The synergistic ratio of RA and AA was 1.72.”

“In vivo, in vitro, prospective, and retrospective epidemiologic inquiries have suggested that retinoids inhibit cancer, and fats have been hypothesized to enhance and ascorbic acid to reduce cancer risk.”

“Abstract L-Ascorbic acid was found to reduce the induction of Epstein-Barr virus-associated antigens in human …–85% of the untreated control culture at concentrations of 100–1000 μM. When such an effect of L-ascorbic acid … retinoic acid known to occur in the … than the latter compound.”

“Further experiments found that AA competes with retinoic acid (RA) to drive cell differentiation in a dose‐dependent manner: AA inhibited neurogenic differentiation and stimulated myogenesis whereas RA did the reverse.”

“Enhanced anti-proliferative effects are seen when vitamin C is administered in conjunction with agents such as retinoic acid [4].”

“In one recent study, the reported synergistic ratio of retinoic acid and vitamin C was 1.72.”

“Strikingly, treatment of differentiating cells with retinoic and ascorbic acid resulted in a twofold increase of dopamine secretion while norepinephrine and epinephrine were decreased.”

“A combination of vitamins C and E (ascorbic acid, tocopherol) or solitary supplementation with vitamin A ( retinoic acid ) prevented lipid-peroxidation.”

“A striking increase in alkaline phosphatase activity (15–20‐fold) was observed in the presence of both ascorbic acid and the highest dose of retinoic acid (10 μM).”

“Addition of retinoic acid to the ascorbic acid‐treated cultures decreased the level of type II collagen synthesis and delayed the induction of types I and X collagen, which were present only after 30 days.”

“fivefold with co-treatment of retinoic and ascorbic acids.”