Acrylamide-induced U937 cell morphological modifications: a comparison between single treatment and coadministration with apoptotic inducine drugs

Acrylamide is a chemical intermediate used in the production and synthesis of polyacrylamides, that are widely used in different fields including food stuffs and cosmetics. Acrylamide may be released into the environment from waste during its production and the manufacture of polyacrilamides and other polymers. There is sufficient evidence for the carcinogenicity of acrylamide in experimental animals, while still inadeguate data are available to evaluate that in humans. In particular, no data are yet available to determine its effect when challenged, on purpose or accidentally, with transformed cells, also in association with apoptotic-inducing drugs or stress. With this in view, the effect of acrylamide was investigated, at morphological level, when given to U937 cells as a single compound or together with apoptotic inducine drugs, like puromycin or H2O2, or with physical stress, like hyperthermia. Human monocytic leucemia U937 cells readly undergo apoptosis when exposed to inhibitors of protein synthesis (puromycin), oxidative stress (H2O2), or heat shock at 43 °C for 1 h, but not to acrylamide 50 m/ml. The simultaneous incubation of cells with both puromycin, H2O2, or heat shock, and with acrylamide significantly affects the apoptotic rate achieved with the single compound. However, for all treatments (single or double) almost all cells showed modification of shape: distortion of roundness, loss of microvilli and formation of large bleb-like protrusions.