title: Inhibition of cyclophosphamide and mitomycin C-induced sister chromatid exchanges in mice by vitamin C.
abstract: Ascorbic acid (vitamin C) is known to act as an antimutagen and anticarcinogen in several test systems. However, there is no report of its effect on carcinogen-induced chromosomal damage in vivo in animals. The present study was performed to determine whether or not ascorbic acid affects sister chromatid exchanges (SCEs) induced by cyclophosphamide (CPA) and mitomycin C (MMC) in bone marrow and spleen cells in mice. The results indicate that ascorbic acid per se did not cause a significant increase in SCEs in mice. However, increasing concentrations of ascorbic acid caused decreasing levels of CPA- and MMC-induced SCEs in both cell types in vivo. At the highest concentration of ascorbic acid, 6.68 g/kg, approximately 75 and 40% SCE inhibition in both cell types was noted for CPA and MMC, respectively. Likewise, under in vivo/in vitro conditions (exposure of animals to experimental chemicals followed by culturing of cells), ascorbic acid caused a dose-related decrease in CPA- and MMC-induced SCEs, up to a dose of 3.34 g/kg At this concentration, approximately 50% CPA- and MMC-induced SCE inhibition was observed in both cell types studied. Thus, ascorbic acid acts as an anti-SCE agent in both in vivo and in vivo/in vitro conditions in mice.
authors.forename: G
authors.initials: G
authors.lastname: Krishna
authors.forename: J
authors.initials: J
authors.lastname: Nath
authors.forename: T
authors.initials: T
authors.lastname: Ong
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D001853:Bone Marrow / Q000187:drug effects; D003520:Cyclophosphamide / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D016685:Mitomycin; D008937:Mitomycins / Q000633:toxicity*; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D013154:Spleen / Q000187:drug effects
chemical_list: D008937:Mitomycins; D016685:Mitomycin; D003520:Cyclophosphamide; D001205:Ascorbic Acid