02931nas a2200421 4500008004100000022001400041245012100055210006900176260001500245490000800260520158600268653001201854653002001866653002501886653001101911653001401922653000901936653002701945653002201972653000901994653002402003653001302027653001402040653003802054100002102092700002702113700001702140700002202157700002702179700002302206700002202229700001902251700002102270700001802291700002502309700002502334856015002359 2021 eng d a1945-717000aExposure to Propylparaben During Pregnancy and Lactation Induces Long-Term Alterations to the Mammary Gland in Mice.0 aExposure to Propylparaben During Pregnancy and Lactation Induces c2021 06 010 v1623 a
The mammary gland is a hormone sensitive organ that is susceptible to endocrine-disrupting chemicals (EDCs) during the vulnerable periods of parous reorganization (ie, pregnancy, lactation, and involution). Pregnancy is believed to have long-term protective effects against breast cancer development; however, it is unknown if EDCs can alter this effect. We examined the long-term effects of propylparaben, a common preservative used in personal care products and foods, with estrogenic properties, on the parous mouse mammary gland. Pregnant BALB/c mice were treated with 0, 20, 100, or 10 000 µg/kg/day propylparaben throughout pregnancy and lactation. Unexposed nulliparous females were also evaluated. Five weeks post-involution, mammary glands were collected and assessed for changes in histomorphology, hormone receptor expression, immune cell number, and gene expression. For several parameters of mammary gland morphology, propylparaben reduced the effects of parity. Propylparaben also increased proliferation, but not stem cell number, and induced modest alterations to expression of ERα-mediated genes. Finally, propylparaben altered the effect of parity on the number of several immune cell types in the mammary gland. These results suggest that propylparaben, at levels relevant to human exposure, can interfere with the effects of parity on the mouse mammary gland and induce long-term alterations to mammary gland structure. Future studies should address if propylparaben exposures negate the protective effects of pregnancy on mammary cancer development.
10aAnimals10aCells, Cultured10aEndocrine Disruptors10aFemale10aLactation10aMale10aMammary Glands, Animal10aMaternal Exposure10aMice10aMice, Inbred BALB C10aParabens10aPregnancy10aPrenatal Exposure Delayed Effects1 aMogus, Joshua, P1 aLaPlante, Charlotte, D1 aBansal, Ruby1 aMatouskova, Klara1 aSchneider, Benjamin, R1 aDaniele, Elizabeth1 aSilva, Shannon, J1 aHagen, Mary, J1 aDunphy, Karen, A1 aJerry, Joseph1 aSchneider, Sallie, S1 aVandenberg, Laura, N uhttps://www.umass.edu/veterinary-animal-sciences/research-faculty/publications/exposure-propylparaben-during-pregnancy-and-lactation-induces-long