FRUCTOSE-INDUCED ENHANCED MITOGENICITY OF DIPLOID HUMAN-CELLS - POSSIBLE RELATIONSHIP WITH CELL-DIFFERENTIATION

Fructose strongly stimulates the growth of normal diploid human skin f ibroblasts (SFs) and induces marked changes in their morphology and li pid accumulation. This mitogenic effect occurs despite very low fructo se consumption and depends on the presence of glutamine. The cell kine tics of cultured fructose-fed human skin fibroblasts were different fr om those fed on glucose: in the presence of fructose a high proliferat ive index persisted at Day 14 of culture and the duration of the total cell cycle and of the G1 + 1/2 M and S phases was slightly shorter. T he mitogenic effect of fructose on SF was largest in die presence of h uman serum: it was small or undetectable when fibroblasts were culture d in media supplemented with dialyzed human serum, fetal bovine serum, or serum substitutes. This suggests that serum growth factor(s) media te the mitogenic effect of fructose. Only normal diploid human cells s eem to be sensitive to this mitogenic effect of fructose: the long-ter m growth of normal human liver cells on fructose was slightly better o r similar to that on glucose. In contrast, fructose could only support limited growth of hamster fibroblastic Nil cells and of a transformed human fibroblastic line, which grew better with glucose.