Increases in DNA and Protein Syntheses in Human Umbilical Vein Endothelial Cells Treated with Asbestos

Increase in DNA and Protein Syntheses in Human Umbilical Vein Endothelial Cells Treated with Asbestos: Yuji KARASAKI, et al. School of Health Sciences, University of Occupational and Environmental Health—When human umbilical vein endothelial cells (HUVECs) were treated with crocidolite asbestos, HUVECs phagocytized the fibers; no cytotoxic effect was observed when treated at concentrations lower than 10 μg/ml for 24 h, 48 h and 72 h. The time-dependent effect of crocidolite asbestos on DNA synthesis and protein synthesis in HUVECs was studied. The DNA synthesis of the cells exhibited the maximum augmentation (150%) at 24 h, and the protein synthesis increased to the maximal value (140%) at 36 h. The dose-dependent effect of crocidolite asbestos on DNA synthesis and protein synthesis in HUVECs was also studied. The maximum increases in DNA synthesis and protein synthesis were observed at 5 μg/ml and at 10 μg/ml of the fibers, respectively. An apparent increase in DNA synthesis may be mainly due to the repair of DNA damage induced by asbestos under our present experimental conditions, but also in part due to the mitogenic effect of asbestos. Cell injury and DNA damage will remain for a while in the cells, and asbestos fibers phagocytized into cells may induce not only specific but also nonspecific gene transcriptions, which might promote mutations in HUVECs and asbestosis.