Effect of lead on fibroblasts taken from an 84-year-old donor

Abstract

Human, diploid fibroblasts from an 84-year-old donor (A1Pos) were used to study the effect of 20, 40 and 80 μg/100 ml concentrations of lead on in vitro senescence. The results showed that there was a significant decrease in the number of total population doublings due to the treatment with lead. However, there was no significant difference between the effects of the three concentrations of lead. As far as nucleolar number is concerned in the case of the controls as well as in the lead-treated cells the number remained constant with aging in vitro. When the areas and dry mass of cells, nuclei and nucleoli were examined in controls and lead-treated groups at early and late doublings the results showed that in general no significant changes were noted with the exception of the 40 μg/100 ml lead treatment which caused a significant increase in these parameters with aging in vitro. The results are discussed and compared to those from a previous study [17] in which embryonic, IMR-90 cells were treated in a similar way. It is concluded that the fibroblasts from the 84-year-old donor A1Pos are even more vulnerable than the embryonic cells to the effects of lead as indicated by the drastic curtailment of the in vitro lifespan exhibited in the case of treatment even with the lowest concentration of lead. The overall lack of significant change seen in nucleolar numbers and area and dry mass measurements as a result of lead treatment is attributed to the fact that the A1Pos cells were nearer than the IMR-90 cells to the end of their in vitro lifespan, had achieved the cytological characteristics of old cells, and therefore did now show much change.