RESUMO
Previously, we found that the ultraviolet filter benzophenone-3 (BP3) causes fetal growth restriction in mice when is applied when implantation occurs (first week of gestation). However, whether BP3 can affect gestation and fertility after implantation period is unknown. We aimed to study the effects on reproductive physiology of the offspring caused by perinatal exposure to BP3. C57BL/6 pregnant mice were dermally exposed to 50 mg BP3/kg bw.day or olive oil (vehicle) from gestation day 9 (gd9) to postnatal day 21 (pnd1). We observed no differences in mother's weights, duration of gestation, number of pups per mother, onset of puberty or sex ratio. The weights of the pups exposed to benzophenone-3 were transiently lower than those of the control. Estrous cycle was not affected by perinatal exposure to BP3. Besides, we performed a fertility assessment by continuous breeding protocol: at 10 weeks of age, one F1 female and one F1 male mouse from each group was randomly chosen from each litter and housed together for a period of 6 months. We noticed a reduction in the number of deliveries per mother among dams exposed to BP3 during the perinatal period. To see if this decreased fertility could be associated to an early onset of oocytes depletion, we estimated the ovarian reserve of germ cells. We found reduced number of oocytes and primordial follicles in BP3. In conclusion, perinatal exposure to BP3 leads to a decline in the reproductive capacity of female mice in a continuous breeding protocol linked to oocyte depletion.
Assuntos
Benzofenonas , Camundongos Endogâmicos C57BL , Oócitos , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Benzofenonas/toxicidade , Benzofenonas/administração & dosagem , Gravidez , Masculino , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Oócitos/efeitos dos fármacos , Camundongos , Fertilidade/efeitos dos fármacos , Protetores Solares/toxicidade , Exposição Materna/efeitos adversosRESUMO
Benzophenone-3 (BP3) is a common ingredient in personal care products (PCPs) due to its well-established effectiveness in absorbing UV radiation. Sunscreen products are among the most widely used PCPs-containing BP3 applied to the skin, resulting in significant human exposure to BP3 primarily through a dermal application. In the present work, we have tested the action of three environmentally relevant concentrations of BP3 (2, 20 and 200 µg/L) on an in vitro model of implantation of murine blastocysts and on migration ability of the human trophoblast cell line Swan 71. We showed that BP3 caused a significant reduction of blastocyst expansion and a delayed hatching in a non-monotonic way. Besides, embryos displayed a delayed attachment in the three BP3 groups, resulting in a smaller implantation area on the 6th day of culture: BP3(2) (0.32 ± 0.07 mm2); BP3(20) (0.30 ± 0.08 mm2) and BP3(200) (0.25 ± 0.06 mm2) in comparison to the control (0.42 ± 0.07 mm2). We also found a reduced migration capacity of the human first-trimester trophoblast cell line Swan 71 in a scratch assay when exposed to BP3: the lowest dose displayed a higher uncovered area (UA) at 6h when compared to the control, whereas a higher UA of the wound was observed for the three BP3 concentrations at 18 and 24 h of exposure. The changes in UA provoked by BP3 restored to normal values in the presence of flutamide, an androgen receptor (AR) inhibitor. These results indicate that a direct impairment on early embryo implantation and a defective migration of extravillous trophoblast cells through the androgen receptor pathway can be postulated as mechanisms of BP3-action on early gestation with potential impact on fetal growth.
Assuntos
Benzofenonas , Movimento Celular , Implantação do Embrião , Protetores Solares , Trofoblastos , Raios Ultravioleta , Benzofenonas/toxicidade , Protetores Solares/toxicidade , Protetores Solares/farmacologia , Trofoblastos/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Camundongos , Animais , Humanos , Implantação do Embrião/efeitos dos fármacos , Blastocisto/efeitos dos fármacos , Feminino , Linhagem CelularRESUMO
The aim of this study was to analyze whether dermal exposure to benzophenone 3 (BP-3) during pregnancy affects critical parameters of pregnancy, and whether this exposure may affect the outcome of a second pregnancy in mice. Pregnant mice were exposed to 50-mg BP-3/kg body weight/day or olive oil (vehicle) from gestation day (gd) 0 to gd6 by dermal exposure. High-frequency ultrasound imaging was used to follow up fetal and placental growth in vivo. Blood flow parameters in uterine and umbilical arteries were analyzed by Doppler measurements. Mice were killed at gd5, gd10, and gd14 on the first pregnancy, and at gd10 and 14 on the second pregnancy. The weight of the first and second progenies was recorded, and sex ratio was analyzed. BP-3 levels were analyzed in serum and amniotic fluid. BP-3 reduced the fetal weight at gd14 and feto-placenta index of first pregnancy, with 16.13% of fetuses under the 5th percentile; arteria uterina parameters showed altered pattern at gd10. BP-3 was detected in serum 4 h after the exposure at gd6, and in amniotic fluid at gd14. Offspring weight of first progeny was lower in BP-3 group. Placenta weights of BP-3 group were decreased in second pregnancy. First and second progenies of mothers exposed to BP-3 showed a higher percentage of females (female sex ratio). Dermal exposure to low dose of BP-3 during early pregnancy resulted in an intrauterine growth restriction (IUGR) phenotype, disturbed sex ratio and alterations in the growth curve of the offspring in mouse model.
Assuntos
Benzofenonas/toxicidade , Desenvolvimento Fetal/efeitos dos fármacos , Retardo do Crescimento Fetal/induzido quimicamente , Razão de Masculinidade , Protetores Solares/toxicidade , Administração Cutânea , Líquido Amniótico/metabolismo , Animais , Benzofenonas/administração & dosagem , Benzofenonas/sangue , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/fisiopatologia , Idade Gestacional , Masculino , Exposição Materna , Troca Materno-Fetal , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Placentação/efeitos dos fármacos , Gravidez , Medição de Risco , Protetores Solares/administração & dosagem , Protetores Solares/metabolismoRESUMO
We describe a detailed protocol to establish a newborn rat whole ovary culture, which enables the study of direct effects (independent of hypothalamic-pituitary-gonadal axis) of endocrine disrupting chemicals (EDCs), such as benzophenone-3 (BP-3). This method is useful to understand changes in follicle formation, primordial to primary transition, and expression of regulatory molecules linked to these processes and also provides an alternative to animal models. © 2019 by John Wiley & Sons, Inc. Basic Protocol 1: Rat ovarian surgery Basic Protocol 2: Whole organ/ovarian culture Basic Protocol 3: RNA isolation and quantitative real-time PCR Basic Protocol 4: Histological processing and staining.