Environmental endocrine disruptors prurification by recombinant pregnane X and estrogen receptor-affinity columns

Abstract : Nuclear Pregnane X Receptor (PXR) is involved in the regulation of drug-metabolism enzymes and therefore plays an essential role in the detoxification pathways. Recent studies have shown that PXR can be activated by exogenous environmental xenobiotics such as pesticides, polychlorinated biphenyls, brominated flame retardants, phyto and myco-estrogens and many more. We measured PXR activity in samples from wastewater treatment and surface water. However, due to the capacity of PXR to bind a multitude of different types of environmental pollutants, it is difficult to predict which type of molecule is responsible for the observed activity in environmental samples. The development of a tool to purify PXR ligands in an environmental complex matrix such as wastewater and sludge should improve their chemical detection. We already developed a recombinant ER alpha affinity column for the purification of estrogenic compounds from water and sediment extracts. In the same way we developed a procedure with immobilized PXR receptor to capture PXR environmental ligands. We showed that this method allowed us to isolate ER and PXR ligands in wastewater, sludge and sediment extracts, and thus facilitate their further analysis