Citrate does not change uranium chemical speciation in cell culture medium but increases its toxicity and accumulation in NRK-52E cells.
Chem Res Toxicol
; 19(12): 1637-42, 2006 Dec.
Article
em En
| MEDLINE
| ID: mdl-17173377
ABSTRACT
Uranium (U), as a heavy metal, is a strong chemical toxicant, which induces the damage to proximal tubule kidney cells. In order to reproduce U toxicity in vitro and to avoid precipitation, it is necessary to complex it with a strong ligand such as bicarbonate before dilution with cell culture medium. It was recently shown, in vitro on the NRK-52E normal renal tubular epithelial cells, that citrate increased the toxicity of U(VI)-bicarbonate complexes. This property was attributed to a change in U speciation, characterized by the occurrence of U(VI)-citrate complexes, which were supposed to be more toxic than U(VI)-bicarbonate. Here, we present the results of extended X-ray absorption fine structure spectroscopy (EXAFS) analyses of the media that were used to expose cells in vitro. Resulting data show that even when citrate is added to the exposure medium, the predominant species is U(VI)-bicarbonate. Nonetheless, citrate increases U(VI) toxicity and accelerates its intracellular accumulation kinetics, without inducing precipitation. This study emphasizes another parameter that modulates U(VI) toxicity for renal tubule cells and further characterizes the mechanisms of U(VI) toxicity.
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Base de dados:
MEDLINE
Assunto principal:
Nitrato de Uranil
/
Citratos
/
Meios de Cultura
Limite:
Animals
Idioma:
En
Revista:
Chem Res Toxicol
Assunto da revista:
TOXICOLOGIA
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
França