In vitro investigation of uranium cytotoxicity after acute exposure of NRK-52E rat renal proximal tubule epithelial cells
Uranium used in the nuclear cycle has raised concerns regarding its potential hazard to animal and human health. It is a well known nephrotoxicant and its nephrotoxicity is mostly due to proximal tubular epithelial cell damage.
Cytotoxicity of uranyl-bicarbonate and -citrate complexes was evaluated after acute exposure of Normal Rat Kidney (NRK-52E) cells. This model is the only available cell line representative of normal rat proximal tubule epitelium, thus allowing comparison of in vitro results to in vivo data. Classical methylthiazol tetrazolium (MTT), lactate dehydrogenase (LDH) and sulforhodamine B tests were used to determine CI50 cytotoxicity indexes, uranium concentration leading to 50% cell death, of these two uranium formulations. Our results show that uranyl complexes cytotoxicity highly depends on the counter ion, and that cytotoxicity is the same, as measured with the three biochemical tests. Results from J-Chess uranium speciation simulation are reported, allowing the determination of uranyle complexes causing its cytotoxicity.