Is bisphenol S a safer alternative to bisphenol A in terms of potential fetal exposure ? Placental transfer across the perfused human placenta.

Flore C. Grandin (1) , Catherine Viguié (2) , Marlène Z. Lacroix (3) , Véronique V. Gayrard-Troy (2) , Hanna Mila (1) , Alice de Place (4, 5) , Christophe Vayssière (5) , Mathieu Morin (5) , Julie Corbett (1) , Cécile Gayrard (1) , Clémence Gely (2) , Pierre-Louis Toutain (6) , Nicole Picard-Hagen (2)

1 ToxAlim - ToxAlim
2 ToxAlim-EXPER - Exposition, Perturbation Endocrino-métabolique et Reproduction
3 InTheRes - Innovations Thérapeutiques et Résistances
4 CHU Toulouse - Centre Hospitalier Universitaire de Toulouse
5 UT3 - Université Toulouse III - Paul Sabatier
6 Royal Veterinary College [London]

The aim of our study was to evaluate the bidirectional transfer of Bisphenol S (BPS) and its main metabolite, BPS Glucuronide (BPSG), using the model of perfused human placenta and to compare the obtained values with those of Bisphenol A (BPA) and BPA Glucuronide. Fourteen placentas at term were perfused in an open dual circuit with deuterated BPS (1 and 5 μM) and non-labelled BPSG (2.5 μM) and a freely diffusing marker antipyrine (800 ng/ml) in the presence of albumin (25 mg/ml). In a second experiment, the potential role of P-glycoprotein in the active efflux of BPS across the placental barrier was studied using the well-established P-glycoprotein inhibitor, PSC833 (2 and 4 μM). Placental transfer of BPS was much lower than that of BPA in both directions. The placental clearance index of BPS in the materno-fetal direction was three times lower than in the opposite direction, strongly suggesting some active efflux transport. However, our results show that P-glycoprotein is not involved in limiting the materno-fetal transfer of BPS. Placental transfer of BPSG in the fetal compartment was almost non-existent indicating that, in the fetal compartment, BPSG originates mainly from feto-placental metabolism. The feto-maternal clearance index for BPSG was 20-fold higher than the materno-fetal index. We conclude that the blood-placental barrier is much more efficient in limiting fetal exposure to BPS than to BPA, indicating that the placenta has a crucial role in protecting the human fetus from BPS exposure.

Mots clés: Bisphenol A; Bisphenol S; Endocrine disruptor

Mots clés: Bisphenol S glucuronide; Human placental transport

Domaines: Sciences du Vivant [q-bio]

Flore C. Grandin, Catherine Viguié, Marlène Z. Lacroix, Véronique V. Gayrard-Troy, Hanna Mila, et al.. Is bisphenol S a safer alternative to bisphenol A in terms of potential fetal exposure ? Placental transfer across the perfused human placenta.. Chemosphere, 2019, 221, pp.471-478. ⟨10.1016/j.chemosphere.2019.01.065⟩. ⟨hal-02626596⟩