calpain and Carcinoma--Embryonal

In order to reveal neurodegeneration elicited by reactive oxygen intermediates (ROI), neuronally differentiated cells from mouse embryonal carcinoma P19 cell line were exposed to hydrogen peroxide (H2O2). Enhanced protein-phosphorylation on tyrosine residues was detectable within 5 min of exposure to H2O2, and gradual rises in intracellular free Ca2+ level and in calpain activity were observed. Furthermore, H2O2 stimulation of differentiated P19 cells for 24 h resulted in morphological alterations in somas as well as neurites. Also, within 6 h of H2O2 treatment DNA fragmentation has been detected. Taken together, these results suggest that oxidative stress induces degradation of cytoskeletal proteins presumably resulting from increased intracellular Ca2+ concentration and subsequent activation of calpain.

Topics: Animals; Apoptosis; Calcium; Calpain; Carcinoma, Embryonal; Cell Differentiation; Enzyme Activation; Hydrogen Peroxide; Kinetics; Mice; Neurons; Oxidative Stress; Phosphoproteins; Phosphotyrosine; Tumor Cells, Cultured