Figure 1.

Effect of aging and MDL72527 on polyamine levels. HepG2 cells cultured in the absence (open column) or presence (filled column) of 20 µM MDL72527 for 3 days (young) and 3 months with serial passage (aged). Polyamine levels were measured as described in the Materials and Methods section. Spermidine (A) and spermine (B) levels were calculated as nmol/mg protein and expressed as mean ± standard deviation (SD) of triplicate determinations. The dots indicate individual data points. * p < 0.05, *** p < 0.005.