Comparative Effects of Di-(2-ethylhexyl)phthalate and Di-(2-ethylhexyl)terephthalate Metabolites on Thyroid Receptors: In Vitro and In Silico Studies

Plasticizers added to polyvinylchloride (PVC) used in medical devices can be released into patients’ biological fluids. Di-(2-ethylhexyl)phthalate (DEHP), a well-known reprotoxic and endocrine disruptor, must replaced by alternative compounds. Di-(2-ethylhexyl) terephthalate (DEHT) is an interesting candidate due its lower migration from PVC lack of reprotoxicity. However, there still data support the safety human metabolites with regard their hormonal properties thyroid system. The effects DEHT on thyroid/hormone receptors (TRs) were compared vitro silico those DEHP. oxidized had no effect T3 whereas 5-hydroxy-mono-(ethylhexyl)phthalate (5-OH-MEHP) appeared primarily agonist for TRs above 0.2 µg/mL synergistic T3. Monoesters (MEHP mono-(2-ethylhexyl)terephthalate, MEHT) also active receptors. In vitro, MEHP was partial between 10 20 µg/mL. MEHT antagonist at non-cytotoxic concentrations (2–5 µg/mL) concentration-dependent manner. results obtained docking consistent T-screen provide additional information preferential affinity monoesters 5-OH-MEHP TRs. This study highlights interactions TRs, confirming interest DEHT.