Perinatal exposure to bisphenol A modifies the transcriptional regulation of the b-Casein gene during secretory activation of the rat mammary gland

ALTAMIRANO GA; RAMOS JG; GOMEZ AL; LUQUE EH; MUÑOZ-DE-TORO M; KASS L

MOLECULAR AND CELLULAR ENDOCRINOLOGY.

ELSEVIER IRELAND LTD

Lugar: Shannon; Año: 2017 vol. 439 p. 407 - 418

0303-7207

With the aim to analyze whether bisphenol A (BPA) modifies b-Casein (b-Cas) synthesis and transcriptional regulation in perinatally exposed animals, here, pregnant F0 rats were orally exposed to 0, 0.6 or 52 mg BPA/kg/day from gestation day 9 until weaning. Then, F1 females were bred and mammary glands were obtained on lactation day 2. Perinatal BPA exposure decreased b-Cas expression without modifying the activation of prolactin receptor. It also decreased the expression of glucocorticoid receptor in BPA52-exposed dams and b1 and a6 integrins as well as dystroglycan in both BPA groups. In addition, BPA exposure altered the expression of histone-modifying enzymes and induced histone modifications and DNA methylation in the promoter, enhancer and exon VII of the b-Cas gene. An impaired crosstalk between the extracellular matrix and lactogenic hormone signaling pathways and epigenetic modifications of the b-Cas gene could be the molecular mechanisms by which BPA decreased b-Cas expression.