References of "Bourguignon, Jean-Pierre"
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See detailTransgenerational effects of exposure to an EDC mixture on maternal behavior and sexual development
Lopez Rodriguez, David ULiege; Delli, Virginia; GERARD, Arlette ULiege et al

Conference (2018, July 17)

Environmental factors such as endocrine disrupting chemicals (EDCs) have been proven to produce transgenerational inherited modifications. A rising public health challenge is to determine the effect of ... [more ▼]

Environmental factors such as endocrine disrupting chemicals (EDCs) have been proven to produce transgenerational inherited modifications. A rising public health challenge is to determine the effect of complex mixtures of EDCs on the developing body throughout generations. In this study we aim to determine the transgenerational effects of a mixture of EDCs on female sexual development and behavior. Female rats were orally exposed from 2 weeks before gestation until weaning to corn oil or a mixture of 14 anti-androgenic and estrogenic EDCs at low doses. Sexual development (sex ratio, vaginal opening (VO), GnRH interpulse interval and estrous cyclicity) as well as maternal behavior were measured from F0 to F3 generation. In utero exposed females (F1) when raising pups, showed an increased time resting alone and decreased time licking and grooming pups. F2 (animals whose germlines were exposed) and F3 exposed animals showed an altered sex ratio in favor of males and F2 and F3 females showed delayed VO. F2 and F3 females followed for estrous cyclicity showed significant alterations of estrous cyclicity characterized by a significant increase in the time spent in estrus and decreased time spent in diestrus. F3 females presented an increased GnRH interpulse interval compared to control. Overall, data shows that gestational exposure to an EDCs mixture can affect maternal behavior and sexual development during several generations. The effects observed in the F3 generation suggest the presence of transgenerational epigenetic mechanisms. [less ▲]

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See detailNeuroendocrine disruption without direct endocrine mode of action: Polychloro-biphenyls (PCBs) and bisphenol A (BPA) as case studies
Pinson, Anneline ULiege; Franssen, Delphine ULiege; Gerard, Amaury ULiege et al

in Comptes Rendus Biologies (2017), 340(9-10), 432-438

Endocrine disruption is commonly thought to be restricted to a direct endocrine mode of action i.e. the perturbation of the activation of a given type of hormonal receptor by its natural ligand ... [more ▼]

Endocrine disruption is commonly thought to be restricted to a direct endocrine mode of action i.e. the perturbation of the activation of a given type of hormonal receptor by its natural ligand. Consistent with the WHO definition of an endocrine disrupter, a key issue is the “altered function(s) of the endocrine system”. Such altered functions can result from different chemical interactions, beyond agonistic or antagonistic effect at a given receptor. Based on neuroendocrine disruption by polychlorinated biphenyls and bisphenol A, this paper proposes different mechanistic paradigms that can result in adverse health effects. They are a consequence of altered endocrine function(s) secondary to chemical interaction with different steps in the physiological regulatory processes, thus accounting for a possibly indirect endocrine mode of action. © 2017 Académie des sciences [less ▲]

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See detailActivational and organizational disruption of folliculogenesis and estrous cycle caused by exposure to Bisphenol A (BPA) during early postnatal or adult life
Lopez Rodriguez, David ULiege; Franssen, Delphine ULiege; GERARD, Arlette ULiege et al

Conference (2017, May 05)

Our previous studies have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing. However, the long-term effects of such low dose ... [more ▼]

Our previous studies have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing. However, the long-term effects of such low dose exposure as well as the effects of adult exposure have not been studied. One day-old and 90 day-old female rats received daily subcutaneous injections of corn oil (vehicle) or BPA (25ng/kg/d or 5mg/kg/d) for 15 days. The early postnatal exposure to both BPA doses significantly decreased the percentage of females with a regular cycle (BPA-25ng: 51±15%; BPA-5mg: 7±7%; OIL: 86±2%). The estrus cycle alterations were characterized by a decrease in time spent in proestrus (BPA-25ng: 13±3%; BPA-5mg: 12±3%; OIL: 18±3%). During adult exposure, both doses caused a disruption of the estrous cycle characterized by a significant decrease in the average time spent in proestrus (BPA-25ng: 19±2%; BPA-5mg: 17±1%; OIL: 23±1%). This effect was transient as the exposed females showed a regular cycle one month after the last dose of BPA. After adult exposure, we also observed a disruption of folliculogenesis characterized by a significant decrease of antral follicles (BPA-25ng: 21±2%; BPA-5mg: 21±2%; OIL: 36±2%) and increase of atretic follicles (BPA-25ng: 24±4%; BPA-5mg: 26±6%; OIL: 15±1%). GnRH secretion measured ex vivo 24h after adult exposure was moderately affected by BPA. Indeed, GnRH interpulse interval was significantly different when comparing animals exposed to the high or low dose of BPA but not when comparingexposed animals to the control group (BPA-25ng: 42.6±0.5; BPA-5mg: 40.2±0.6%; OIL: 41.1±0,2minutes±SEM). In conclusion, while exposure to BPA produces persistent alterations of the estrous cycle after early postnatal exposure, exposure during adulthood appears to cause activational non-persistent alternations of both the estrous cycle and folliculogenesis. [less ▲]

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See detailEarly postnatal and adult exposure to BPA: activational vs organizational disruption of folliculogenesis and estrous cycle
Lopez Rodriguez, David ULiege; Franssen, Delphine ULiege; GERARD, Arlette ULiege et al

Conference (2017)

Aim: Our society is facing a public health problem linked to the production of endocrine disrupting chemicals (EDCs) (1). In our laboratory we have shown that an early postnatal exposure to a very low ... [more ▼]

Aim: Our society is facing a public health problem linked to the production of endocrine disrupting chemicals (EDCs) (1). In our laboratory we have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing (2). However, the long-term and adult effects of such low doses have not been studied. Methods: one day-old and 90 day-old female rats received daily subcutaneous injections of corn oil (vehicle) or BPA (25ng/kg/day or 5mg/kg/day) for 15 days. For early postnatal exposure, estrous cyclicity was followed until P105 when folliculogenesis was studied. For adult exposure, estrous cyclicity was followed from two weeks before to four weeks after the exposure. Folliculogenesis was studied both 24h and 30 days after the adult BPA exposure. GnRH frequency was measure 24h after the adult BPA exposure. Results: early postnatal exposure to both BPA doses significantly decreased the percentage of females with a regular cycle (BPA-25ng: 51±15%; BPA-5mg: 7±7%; OIL: 86±2%). Folliculogenesis showed a significant decrease in the number of primordial follicles (BPA-25ng: 15.5±3.6; BPA-5mg: 20.4±5.2; OIL: 71.2±14.1) as well as a disruption in atretic follicles (BPA-25ng: 26.5±3.9; BPA-5mg: 111.9±29.4; OIL: 48.8±10.3) and the presence of cysts follicles (BPA-25ng: 0.04±0.02; BPA-5mg: 0.3±0.1). Adult exposure to BPA caused a disruption of the estrous cycle characterized by a significant decrease in the average time spent in proestrus (BPA-25ng: 19±2%; BPA-5mg: 17±1%; OIL: 23±1%). We also observed a disruption of folliculogenesis characterized by a significant decrease of antral follicles (BPA-25ng: 0.4±0.1; BPA-5mg: 0.5±0.07; OIL: 1.54±0.2), an increase of atretic follicles (BPA-25ng: 50.8±7.7; BPA-5mg: 48.7±6.7; OIL: 31.3±5.4) and the presence of cysts follicles (BPA-25ng: 0.2±0.1; BPA-5mg: 0.06±0.02). This effect was transient as the exposed females showed a regular cycle and folliculogenesis one month after the last dose of BPA. GnRH interpulse interval was significantly different when comparing animals exposed to the high or low dose of BPA but not when compared to the control group (BPA-25ng: 42.6±0.5; BPA-5mg: 40.2±0.6%; OIL: 41.1±0,2minutes±SEM). Conclusion: both early postnatal and adult exposure to BPA disrupts the estrous cycle and folliculogenesis. However, while adult exposure produces persistent alterations, the adult exposure cause activational effects. [less ▲]

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See detailEarly exposure to Aroclor 1254 in vivo disrupts the functional synaptic development of newborn hippocampal granule cells.
Parent, Anne-Simone ULiege; Pinson, Anneline ULiege; Woods, N. et al

in European Journal of Neuroscience (2016), 44(12), 3001-3010

Neurogenesis in the dentate gyrus is sensitive to endogenous and exogenous factors that influence hippocampal function. Ongoing neurogenesis and the integration of these new neurons throughout life thus ... [more ▼]

Neurogenesis in the dentate gyrus is sensitive to endogenous and exogenous factors that influence hippocampal function. Ongoing neurogenesis and the integration of these new neurons throughout life thus may provide a sensitive indicator of environmental stress. We examined the effects of Aroclor 1254 (A1254), a mixture of polychlorinated biphenyls (PCBs), on the development and function of newly generated dentate granule cells. Early exposure to A1254 has been associated with learning impairment in children, suggesting potential impact on the development of hippocampus and/or cortical circuits. Oral A1254 (from the 6th day of gestation to postnatal day 21) produced the expected increase in PCB levels in brain at postnatal day 21, which persisted at lower levels into adulthood. A1254 did not affect the proliferation or survival of newborn neurons in immature animals nor did it cause overt changes in neuronal morphology. However, A1254 occluded the normal developmental increase in sEPSC frequency in the third post-mitotic week without altering the average sEPSC amplitude. Our results suggest that early exposure to PCBs can disrupt excitatory synaptic function during a period of active synaptogenesis, and thus could contribute to the cognitive effects noted in children exposed to PCBs. [less ▲]

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See detailExposure to endocrine disrupting chemicals and neurodevelopmental alterations.
Pinson, Anneline ULiege; Bourguignon, Jean-Pierre ULiege; Parent, Anne-Simone ULiege

in Andrology (2016), 4(4), 706-22

The developing brain is remarkably malleable as neural circuits are formed and these circuits are strongly dependent on hormones for their development. For those reasons, the brain is very vulnerable to ... [more ▼]

The developing brain is remarkably malleable as neural circuits are formed and these circuits are strongly dependent on hormones for their development. For those reasons, the brain is very vulnerable to the effects of endocrine-disrupting chemicals (EDCs) during critical periods of development. This review focuses on three ubiquitous endocrine disruptors that are known to disrupt the thyroid function and are associated with neurobehavioral deficits: polychlorinated biphenyls, polybrominated diphenyl ethers, and bisphenol A. The human and rodent data suggesting effects of those EDCs on memory, cognition, and social behavior are discussed. Their mechanisms of action go beyond relative hypothyroidism with effects on neurotransmitter release and calcium signaling. [less ▲]

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See detailAdult exposure to BPA causes activational disruption of estrous cycle and folliculogenesis
Lopez Rodriguez, David ULiege; Franssen, Delphine ULiege; GERARD, Arlette ULiege et al

Conference (2016)

Our society is facing a public health challenge caused by the increasing presence of endocrine disrupting chemicals (EDCs). Bisphenol A (BPA) is a widespread EDC used in the manufacture of PVC and epoxy ... [more ▼]

Our society is facing a public health challenge caused by the increasing presence of endocrine disrupting chemicals (EDCs). Bisphenol A (BPA) is a widespread EDC used in the manufacture of PVC and epoxy resins. While early postnatal exposure to BPA disrupts sexual maturation andpubertal timing, , its effects on fertility after adult exposure have not yet been studied. Female Wistar rats were exposed for 15 days to corn oil or a low (25ng/kg/d) or a high (5mg/kg/d) BPA dose subcutateouslyat 90 days of age. Animals exposed to both doses showed a disruption of the estrous cyclicity characterized by a decrease in the average time spent in proestrus. We observed a disruption on folliculogenesis characterized by a significant decrease of antral follicles and increase of atretic follicles. The exposed females showed a regular cycle one month after the last dose of BPAWe did not observe any difference in the frequency or amplitude of GnRH secretion 24h after the end of exposure. We also observed that early postnatal exposure to BPA for 15 days disrupted estrous cycle during adulthood with a decrease in time spent in proestrus. In conclusion, exposure to BPA neonatally or during adulthood disrupts the estrous cycle and folliculogenesis. The effects of exposure to BPA during adulthood might be independent of GnRH secretion. Moreover, the effects of early postnatal exposure to BPA are persistent while exposure to BPA during adulthood appears to causeeactivational, non persistent alteration of the oestrus cycle. [less ▲]

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See detailActivational and organizational disruption of folliculogenesis and estrous cycle after an exposure to Bisphenol A (BPA) during early postnatal or adult window of exposure
Lopez Rodriguez, David ULiege; Franssen, Delphine ULiege; GERARD, Arlette ULiege et al

Poster (2016)

The increasing presence of endocrine disruption chemicals (EDCs) has been link with a reduction in fertility rate and alterations of pubertal timing. Bisphenol A (BPA) is a ubiquitous EDC used in the ... [more ▼]

The increasing presence of endocrine disruption chemicals (EDCs) has been link with a reduction in fertility rate and alterations of pubertal timing. Bisphenol A (BPA) is a ubiquitous EDC used in the manufacture of polyvinyl chloride (PVC) and epoxy resins that we can find in food containers and plastics. Our previous studies have shown that an early postnatal exposure to a low dose of BPA disrupts sexual maturation and pubertal timing. However, its long-term and adult effects on fertility have not yet been studied. Daily s.c injections of BPA were administered for 15 days to 1 and 90 day-old female Wistar rats at two different doses: a low dose of 25ng/kg/d and a high dose of 5mg/kg/d. The early postnatal exposure to both BPA doses produces a decrease in the percentage of female with a regular cycle characterized by a decrease on the time spend in proestrus (BPA-25ng 13,6±3,4; BPA-5mg 12,2±3,1%; OIL 18,7±3,2%). During exposure at adulthood, both doses caused a disruption of the estrous cycle characterized by a significant decrease in the average time spent in proestrus (BPA-25ng 18,9±2,2%; BPA-5mg 16,9±1,3%; OIL 23,3±0,9%). This effect was We also observed a disruption of folliculogenesis characterized by a significant decrease of antral follicles (BPA-25ng 21,4±2.1%; BPA-5mg 20,94±2%; OIL 35,6±1,6%) and increase of atretic follicles (BPA-25ng 24,2±3,9%; BPA-5mg 26,2±6,3%; OIL 15,5±0,8%). The exposed females showed a regular cycle one month after the last dose of BPA. In conclusion, both BPA doses have been found to produce a disruption of oestrus cycle and folliculogenesis depending on the window of exposure. While BPA produces persistent effects after early postnatal exposure, exposure during adulthood appears to cause activational, non-persistent alterations. [less ▲]

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See detailPuberty from bench to clinic
Bourguignon, Jean-Pierre ULiege; Parent, Anne-Simone ULiege

Book published by Karger (2016)

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See detailDelayed neuroendocrine sexual maturation in female rats after a very low dose of Bisphenol A through altered GABAergic neurotransmission and opposing effects of a high dose.
Franssen, Delphine ULiege; GERARD, Arlette ULiege; HENNUY, Benoit ULiege et al

in Endocrinology (2016)

Rat sexual maturation is preceded by a reduction of the interpulse interval (IPI) of gonadotropinreleasing hormone (GnRH) neurosecretion. This work aims at studying disruption of that neuroendocrine event ... [more ▼]

Rat sexual maturation is preceded by a reduction of the interpulse interval (IPI) of gonadotropinreleasing hormone (GnRH) neurosecretion. This work aims at studying disruption of that neuroendocrine event in females after early exposure to a very low dose of Bisphenol A (BPA), a ubiquitous endocrine disrupting chemical. Female rats were exposed to vehicle or BPA 25 ng/kg.day, 25 g/kg.day, or 5 mg/kg.day from postnatal day (PND) 1 to 5 or 15. Exposure to 25 ng/kg.day of BPA for 5 or 15 days was followed by a delay in developmental reduction of GnRH IPI studied ex vivo on PND 20. After 15 days of exposure to that low dose of BPA, vaginal opening tended to be delayed. In contrast, exposure to BPA 5 mg/kg.day for 15 days resulted in a premature reduction inGnRHIPI and a trend toward early vaginal opening. RNAseq analysis on PND20 indicated that exposure to BPA resulted in opposing dose effectsonthemRNAexpression of hypothalamic genes involved inGABAA neurotransmission. The study of GnRH secretion in vitro in the presence of GABAA receptor agonist/antagonist confirmed an increased or a reduced GABAergic tone after in vivo exposure to the very low or the high dose of BPA, respectively. Overall, we show for the first time that neonatal exposure to BPA leads to opposing dose-dependent effects on the neuroendocrine control of puberty in the female rat. A very low and environmentally relevant dose of BPA delays neuroendocrine maturation related to puberty through increased inhibitory GABAergic neurotransmission. [less ▲]

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See detailCurrent Changes in Pubertal Timing: Revised Vision in Relation with Environmental Factors Including Endocrine Disruptors.
Parent, Anne-Simone ULiege; Franssen, Delphine ULiege; Fudvoye, Julie ULiege et al

in Endocrine Development (2016), 29

The aim of this chapter is to revise some common views on changes in pubertal timing. This revision is based on recent epidemiological findings on the clinical indicators of pubertal timing and data on ... [more ▼]

The aim of this chapter is to revise some common views on changes in pubertal timing. This revision is based on recent epidemiological findings on the clinical indicators of pubertal timing and data on environmental factor effects and underlying mechanisms. A current advancement in timing of female puberty is usually emphasized. It appears, however, that timing is also changing in males. Moreover, the changes are towards earliness for initial pubertal stages and towards lateness for final stages in both sexes. Such observations indicate the complexity of environmental influences on pubertal timing. The mechanisms of changes in pubertal timing may involve both the central neuroendocrine control and peripheral effects at tissues targeted by gonadal steroids. While sufficient energy availability is a clue to the mechanism of pubertal development, changes in the control of both energy balance and reproduction may vary under the influence of common determinants such as endocrine-disrupting chemicals (EDCs). These effects can take place right before puberty as well as much earlier, during fetal and neonatal life. Finally, environmental factors can interact with genetic factors in determining changes in pubertal timing. Therefore, the variance in pubertal timing is no longer to be considered under absolutely separate control by environmental and genetic determinants. Some recommendations are provided for evaluation of EDC impact in the management of pubertal disorders and for possible reduction of EDC exposure along the precautionary principle. [less ▲]

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See detailThe effects of perinatal exposure to polychlorinated biphenyls on hippocampal neurogenesis
Pinson, Anneline ULiege; Parent, Anne-Simone ULiege; chatzi, christina et al

Poster (2015, May)

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See detailPromotion of physical activity among children and adolescents followed for overweight or obesity in
DEWANDRE, Anne-Cécile ULiege; HARVENGT, Julie ULiege; LAGASSE, Celine ULiege et al

in Tijdschrift van de Belgische Kinderarts (2015, January), 17(1), 40

Detailed reference viewed: 70 (17 ULiège)