Molecular mechanisms involved in the non-monotonic effect of bisphenol-a on ca2+entry in mouse pancreatic beta-cells

作者：Villar Pazos Sabrina; Martinez Pinna Juan; Castellano Munoz Manuel; Alonso Magdalena Paloma; Marroqui Laura; Quesada Ivan; Gustafsson Jan Ake; Nadal Angel^*

来源：Scientific Reports, 2017, 7(1): 11770.

DOI：10.1038/s41598-017-11995-3

In regulatory toxicology, the dose-response relationship is a key element towards fulfilling safety assessments and satisfying regulatory authorities. Conventionally, the larger the dose, the greater the response, following the dogma "the dose makes the poison". Many endocrine disrupting chemicals, including bisphenol-A (BPA), induce non-monotonic dose response (NMDR) relationships, which are unconventional and have tremendous implications in risk assessment. Although several molecular mechanisms have been proposed to explain NMDR relationships, they are largely undemonstrated. Using mouse pancreatic beta-cells from wild-type and oestrogen receptor ER beta-/-mice, we found that exposure to increasing doses of BPA affected Ca2+ entry in an NMDR manner. Low doses decreased plasma membrane Ca2+ currents after downregulation of Cav2.3 ion channel expression, in a process involving ER beta. High doses decreased Ca2+ currents through an ER beta-mediated mechanism and simultaneously increased Ca2+ currents via oestrogen receptor ERa. The outcome of both molecular mechanisms explains the NMDR relationship between BPA and Ca2+ entry in beta-cells.

• 出版日期2017-9-18