Collagen synthesis in cultured human skin fibroblasts: effect of ascorbic acid and its analogs.
In confluent human skin fibroblasts maintained in 0.5% serum-supplemented medium. L-ascorbate specifically stimulated the rate of incorporation of labeled proline into total collagenase-sensitive protein, without changing the specific activity of the intracellular free proline. This influence of ascorbate reached a maximum at 30 microM and continued for at least 4 days, resulting in a 4-fold increase. The ascorbate effect occurred in cells at both confluent and subconfluent densities and was evident at all serum concentrations from 0.5-20%. The effect was independent of duration of the radioactive pulse between 2-6 h. D-Ascorbate, D-isoascorbate, and L-dehydroascorbate also stimulated collagen synthesis but at considerably higher concentrations, i.e., 250-300 microM. The stimulation of collagen synthesis by ascorbate and its analogs was accompanied by a decline in prolyl hydroxylase activity and a rise in lysyl hydroxylase activity; again L-ascorbate was found to be most effective. Dimethyltetrahydropterine and L-lactate failed to produce these effects.
D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D003094:Collagen / Q000096:biosynthesis*; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008240:Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase / Q000378:metabolism; D011393:Procollagen-Proline Dioxygenase / Q000378:metabolism; D012867:Skin / Q000187:drug effects / Q000378:metabolism*
D003094:Collagen; D011393:Procollagen-Proline Dioxygenase; D008240:Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase; C030606:proline, 2-oxoglutarate 3-dioxygenase; D001205:Ascorbic Acid