References of "Blacher, Silvia"
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See detailEstetrol combined to progestogen for menopause or contraception indication is neutral on breast cancer
Gallez, Anne ULiege; Blacher, Silvia ULiege; Maquoi, Erik ULiege et al

in Cancers (2021)

Hormonal treatments, especially those used to treat menopause symptoms are known to increase breast cancer risk. It is thus necessary to identify new formulations with a better benefit/risk pro-file. The ... [more ▼]

Hormonal treatments, especially those used to treat menopause symptoms are known to increase breast cancer risk. It is thus necessary to identify new formulations with a better benefit/risk pro-file. The aim of this translational study was to evaluate the breast cancer risk associated to a combination of a natural estrogen, named estetrol, with progestogens such as natural progesterone and drospirenone. Since the assessment of breast cancer risk in patients during drug development is not possible given the requirement of long-term studies in large populations, this study provides new evidences that a therapeutic dose of estetrol for menopause treatment or contraception, combined with progesterone or drospirenone, may provide a better benefit/risk profile towards breast cancer risk compared to hormonal treatments currently available for patients. [less ▲]

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See detailTumor exposed-lymphatic endothelial cells promote primary tumor growth via IL6.
Van de Velde, Maureen; Ebroin, Marie ULiege; Durré, Tania ULiege et al

in Cancer Letters (2021), 497

Solid tumors are composed of tumor cells and stromal cells including lymphatic endothelial cells (LEC), which are mainly viewed as cells forming lymphatic vessels involved in the transport of metastatic ... [more ▼]

Solid tumors are composed of tumor cells and stromal cells including lymphatic endothelial cells (LEC), which are mainly viewed as cells forming lymphatic vessels involved in the transport of metastatic and immune cells. We here reveal a new mechanism by which tumor exposed-LEC (teLEC) exert mitogenic effects on tumor cells. Our conclusions are supported by morphological and molecular changes induced in teLEC that in turn enhance cancer cell invasion in 3D cultures and tumor cell proliferation in vivo. The characterization of teLEC secretome by RNA-Sequencing and cytokine array revealed that interleukine-6 (IL6) is one of the most modulated molecules in teLEC, whose production was negligible in unexposed LEC. Notably, neutralizing anti-human IL6 antibody abrogated teLEC-mediated mitogenic effects in vivo, when LEC were mixed with tumor cells in the ear sponge assay. We here assign a novel function to teLEC that is beyond their role of lymphatic vessel formation. This work highlights a new paradigm, in which teLEC exert "fibroblast-like properties", contribute in a paracrine manner to the control of tumor cell properties and are worth considering as key stromal determinant in future studies. [less ▲]

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See detailPyruvate dehydrogenase kinase/lactate axis: a therapeutic target for neovascular age-related macular degeneration identified by metabolomics
LAMBERT, Vincent ULiege; hansen, Sylvain; Schoumacher, Matthieu ULiege et al

in Journal of Molecular Medicine (2020)

Neovascular age-related macular degeneration (nAMD) is the leading cause of blindness in aging populations. Here, we applied metabolomics to human sera of patients with nAMD during an active (exudative ... [more ▼]

Neovascular age-related macular degeneration (nAMD) is the leading cause of blindness in aging populations. Here, we applied metabolomics to human sera of patients with nAMD during an active (exudative) phase of the pathology and found higher lactate levels and a shift in the lipoprotein profile (increased VLDL-LDL/HDL ratio). Similar metabolomics changes were detected in the sera of mice subjected to laser-induced choroidal neovascularization (CNV). In this experimental model, we provide evidence for two sites of lactate production: first, a local one in the injured eye, and second a systemic site associated with the recruitment of bone marrow–derived inflammatory cells. Mechanistically, lactate promotes the angiogenic response and M2-like macrophage accumulation in the eyes. The therapeutic potential of our findings is demonstrated by the pharmacological control of lactate levels through pyruvate dehydrogenase kinase (PDK) inhibition by dichloroacetic acid (DCA). Mice treated with DCA exhibited normalized lactate levels and lipoprotein profiles, and inhibited CNV formation. Collectively, our findings implicate the key role of the PDK/lactate axis in AMD pathogenesis and reveal that the regulation of PDK activity has potential therapeutic value in this ocular disease. The results indicate that the lipoprotein profile is a traceable pattern that is worth considering for patient follow-up. [less ▲]

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See detailLiposomes and drug-in-cyclodextrin-in-liposomes formulations encapsulating 17β-estradiol: an innovative drug delivery system that prevents the activation of the membrane-initiated steroid signaling (MISS) of estrogen receptor α
Gallez, Anne ULiege; Palazzo, Claudio ULiege; Blacher, Silvia ULiege et al

in International Journal of Pharmaceutics (2020), 573

The encapsulation into liposomes of several types of molecules presents the advantages to protect the activity of these molecules and to target specific tissues. Nevertheless, a major obstacle remains the ... [more ▼]

The encapsulation into liposomes of several types of molecules presents the advantages to protect the activity of these molecules and to target specific tissues. Nevertheless, a major obstacle remains the incomplete understanding of nano-bio interactions. Specifically, the impact that inclusion of drug into liposomes or of drug-in-cyclodextrin-in liposomes (DCL) could have on the molecular and cellular mechanism of drug action is largely unknown. As a proof of concept, we evaluated the impact of 17β-estradiol (E2) included into liposomes or DCL on estrogen receptor (ER)α signaling pathways. Indeed, ERα relays the pleiotropic actions of E2 in physiology and pathophysiology through two major pathways: (1) the genomic/nuclear effects associated to the transcriptional activity of the ERα and (2) the rapid/nongenomic/membrane-initiated steroid signaling (MISS) effects related to the induction of fast signaling pathways occurring when ERα is anchored to the plasma membrane. We evidenced that the inclusion of E2 into liposomes (Lipo-E2) or into DCL (DCL-E2) prevented the activation of the rapid/nongenomic/extranuclear/MISS pathway of ERα, while the activation of the genomic/nuclear pathway was maintained. These results support that Lipo-E2 and DCL-E2 could be a useful tool to delineate the complex molecular mechanisms associated to ERα. In conclusion, this study supports the notion that inclusion of drugs into liposomes or DCL could modify some specific pathways of their molecular and cellular mechanisms of action. These results emphasized that attention should be paid to nano-bio interactions induced by the use of nanovectors in medicine. [less ▲]

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See detailImpact of cancer associated fibroblasts-derived cathepsin B on breast cancer progression
Bourgot, Isabelle ULiege; Louis, Thomas ULiege; Kasabova, Mariana et al

Poster (2019, September 20)

Tumors arise in a complex ecosystem gover ned by interactions established between cancer cells and the microenvironment. This one is constituted on one side by a multitude of different non-cancerous cell ... [more ▼]

Tumors arise in a complex ecosystem gover ned by interactions established between cancer cells and the microenvironment. This one is constituted on one side by a multitude of different non-cancerous cell types (e.g.: stromal and immune cells) and on the other side by components of the extracellular matrix. During cancerogenesis fibroblasts are activated and differenciated into cancer associated fibroblasts (CAFs). Nevertheless, the precise functions of CAFs in cancer progression are not fully understood. Among proteases implicated in both ECM remodeling and cancer progression, cathepsin B (Ctsb), a lysosomial cystein protease, has been detected in cancer cells and in tumor-associated macrophages. Ctsb expression is associated with a poor prognosis in breast cancer patients. However, the contribution of CAF-derived Ctsb to tumor progression is unknown. By using the MMTV-PyMT mouse model of breast cancer, our preliminary data reveal that CAFs express Ctsb at higher levels than cancer cells. Our data show that Ctsb deficiency impairs the capacity of CAFs to interact with collagen fibers and strongly diminishes the migration of CAFs in a 3D spheroid model. Further more, we demonstrate that the invasion of Ctsb-/- CAFs is restored upon addition of conditioned medium collected from WT CAFs but Further more, the invasion of Ctsb-/- CAFs is restored upon addition of conditioned medium collected from wild-type (WT) CAFs but also by durotaxis or by deletion of Cathepsin Z (Ctsz). Collectively these data suggest that Ctsb represents a key regulator of the complex cross-talk established between CAFs, the ECM and cancer cells. [less ▲]

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See detailProgrammed death–ligand 1 and vimentin: A tandem marker as prognostic factor in NSCLC
Ancel, J.; Birembaut, P.; de Wolf, Maxime et al

in Cancers (2019), 11(10), 1411

In non-metastatic non-small-cell lung cancer (NSCLC), outcomes remain poor. Adjuvant chemotherapies provide a limited improvement in disease-free survival. Recent exploratory studies on early-stage NSCLC ... [more ▼]

In non-metastatic non-small-cell lung cancer (NSCLC), outcomes remain poor. Adjuvant chemotherapies provide a limited improvement in disease-free survival. Recent exploratory studies on early-stage NSCLC show that immunotherapy given according to Programmed Death–Ligand 1 expression generates variable results, emphasizing a need to improve tumor characterization. We aimed to conjointly assess NSCLC, the expression of PD–L1, and epithelial–mesenchymal transition, frequently involved in tumor aggressiveness. 188 resected NSCLCs were analyzed. Among 188 patients with curatively resected NSCLC, 127 adenocarcinomas and 61 squamous cell carcinomas were stained for PD–L1 and vimentin expression. Overall survival has been compared regarding PD–L1 and vimentin statuses both separately and conjointly in Tumor Cancer Genome Atlas databases. PD–L1 and vimentin higher expressions were strongly associated (OR = 4.682, p < 0.0001). This co-expression occurred preferentially in tumors with lymph node invasion (p = 0.033). PD–L1 was significantly associated with high EMT features. NSCLC harboring both PD–L1high/vimentinhigh expressions were significantly associated with poor overall survival (p = 0.019). A higher co-expression of vimentin and PD–L1 was able to identify patients with worse outcomes. Similar to an important prognostic marker in NSCLC, this tandem marker needs to be further presented to anti-PD–L1 immunotherapies to improve outcome. © 2019 by the authors. Licensee MDPI, Basel, Switzerland. [less ▲]

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See detailImpact of cancer associated fibroblasts-derived cathepsin B on breast cancer progression
Bourgot, Isabelle ULiege; Louis, Thomas; Kasabova, Mariana et al

Conference (2019, September 19)

Tumors arise in a complex ecosystem gover ned by interactions established between cancer cells and the microenvironment. This one is constituted on one side by a multitude of different non-cancerous cell ... [more ▼]

Tumors arise in a complex ecosystem gover ned by interactions established between cancer cells and the microenvironment. This one is constituted on one side by a multitude of different non-cancerous cell types (e.g.: stromal and immune cells) and on the other side by components of the extracellular matrix. During cancerogenesis fibroblasts are activated and differenciated into cancer associated fibroblasts (CAFs). Nevertheless, the precise functions of CAFs in cancer progression are not fully understood. Among proteases implicated in both ECM remodeling and cancer progression, cathepsin B (Ctsb), a lysosomial cystein protease, has been detected in cancer cells and in tumor-associated macrophages. Ctsb expression is associated with a poor prognosis in breast cancer patients. However, the contribution of CAF-derived Ctsb to tumor progression is unknown. By using the MMTV-PyMT mouse model of breast cancer, our preliminary data reveal that CAFs express Ctsb at higher levels than cancer cells. Our data show that Ctsb deficiency impairs the capacity of CAFs to interact with collagen fibers and strongly diminishes the migration of CAFs in a 3D spheroid model. Further more, we demonstrate that the invasion of Ctsb-/- CAFs is restored upon addition of conditioned medium collected from WT CAFs but Further more, the invasion of Ctsb-/- CAFs is restored upon addition of conditioned medium collected from wild-type (WT) CAFs but also by durotaxis or by deletion of Cathepsin Z (Ctsz). Collectively these data suggest that Ctsb represents a key regulator of the complex cross-talk established between CAFs, the ECM and cancer cells. [less ▲]

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See detailStromal integrin alpha11 regulates PDGFR-beta signaling and promotes breast cancer progression.
Primac, Irina ULiege; Maquoi, Erik ULiege; Blacher, Silvia ULiege et al

in Journal of Clinical Investigation (2019), 130

Cancer-associated fibroblasts (CAFs) are key actors in modulating the progression of many solid tumors such as breast cancer (BC). Herein, we identify an integrin alpha11/PDGFRbeta+ CAF subset displaying ... [more ▼]

Cancer-associated fibroblasts (CAFs) are key actors in modulating the progression of many solid tumors such as breast cancer (BC). Herein, we identify an integrin alpha11/PDGFRbeta+ CAF subset displaying tumor-promoting features in BC. In the preclinical MMTV-PyMT mouse model, integrin alpha11-deficiency led to a drastic reduction of tumor progression and metastasis. A clear association between integrin alpha11 and PDGFRbeta was found at both transcriptional and histological levels in BC specimens. High stromal integrin alpha11/PDGFRbeta expression was associated with high grades and poorer clinical outcome in human BC patients. Functional assays using five CAF subpopulations (one murine, four human) revealed that integrin alpha11 promotes CAF invasion and CAF-induced tumor cell invasion upon PDGF-BB stimulation. Mechanistically, integrin alpha11 pro-invasive activity relies on its ability to interact with PDGFRbeta in a ligand-dependent manner and to promote its downstream JNK activation, leading to the production of tenascin C, a pro-invasive matricellular protein. Pharmacological inhibition of PDGFRbeta and JNK impaired tumor cell invasion induced by integrin alpha11-positive CAFs. Collectively, our study uncovers an integrin alpha11-positive subset of pro-tumoral CAFs that exploits PDGFRbeta/JNK signalling axis to promote tumor invasiveness in BC. [less ▲]

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See detailOzone-primed neutrophils promote early steps of tumor cell metastasis to lungs by enhancing their NET production
Rocks, Natacha ULiege; Vanwinge, Céline ULiege; Radermecker, Coraline ULiege et al

in Thorax (2019), 0

Air pollution, including particulates and gazes such as ozone (O3), is detrimental for patient’s health and has repeatedly been correlated to increased morbidity and mortality in industrialized countries ... [more ▼]

Air pollution, including particulates and gazes such as ozone (O3), is detrimental for patient’s health and has repeatedly been correlated to increased morbidity and mortality in industrialized countries. Although studies have described a link between ambient particulate matter and increased lung cancer morbidity, no direct relation has yet been established between O3 exposure and metastatic dissemination to lungs. [less ▲]

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See detailContralateral vascularized lymph node transfer : an optimized mouse model
VOTTERO, Giulia ULiege; MORFOISSE, Florent; Durré, Tania ULiege et al

in Journal of Reconstructive Microsurgery Open (2019), 4

Detailed reference viewed: 42 (4 ULiège)
See detailEffects of exposure to an EDC mixture on the pubertal timing through a maternal behavioral epigenetic multigenerational transmission
Lopez Rodriguez, David ULiege; Delli, Virginia; GERARD, Arlette ULiege et al

Conference (2019)

Endocrine disrupting chemicals (EDCs) are today a rising public health challenge because of their ubiquity and presence in complex mixtures and their effects on the developing body throughout generations ... [more ▼]

Endocrine disrupting chemicals (EDCs) are today a rising public health challenge because of their ubiquity and presence in complex mixtures and their effects on the developing body throughout generations. We aim at studying the effect of a mixture of EDCs on female sexual development during 3 generations of females after exposure and determine whether an epigenetic hypothalamic mechanism is involved in those effects. 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 (F0 generation). Sexual development (vaginal opening, GnRH interpulse interval and estrous cyclicity) as well as maternal behavior were measured from F1 to F3 generation. An RNAseq was carry out using mediobasal hypothalamus from females at P21 from the F1 and F3 generation to decipher targets of the exposure, then validated by RT-PCR and studied for epigenetic modifications by ChIP. F2 and F3 females showed a delayed puberty (delayed VO) and a decrease in the percentage of females having regular estrous cycles, characterized by a significant increase in the time spent in estrus and decreased time spent in diestrus. A hypothalamic epigenetic mechanism is known to be involved in the onset of puberty. We have observed both transcriptional and histone epigenetic alterations in genes involved in estrogen (ESR1), glutamtergic (GRIN2Dà and dopamine (TH and DRD1) signaling as well as in glucocorticoid activity (NR3C1 and CRH), kisspeptin (KISS1) and oxytocin (OXT). We have as well observed that F1 females, exposed in utero, which shows a decrease in TH mRNA expression spent less time licking and more time resting alone. Those modifications on maternal behavior are known to be transmitted through generations. Overall, data shows that gestational exposure to an EDCs mixture can affect maternal behavior and sexual development during several generations. The F1 alteration of maternal behavior caused by in utero exposure to the mixture of EDCs trigger a multigenerational transmission of the phenotype and an induces an altered epigenetic reprogramming if the hypothalamus. [less ▲]

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See detailEDC mixture disrupts maternal behavior and the hypothalamic control of puberty transgenerationally through epigenetic mechanisms.
Lopez Rodriguez, David ULiege; Alwin, Carlos Francisco; GERARD, Arlette ULiege et al

Poster (2019)

Endocrine disrupting chemicals (EDCs) are a rising concern for public health due to their ubiquity as complex mixtures. Our goal was to study the effect of an EDC mixture on female sexual development ... [more ▼]

Endocrine disrupting chemicals (EDCs) are a rising concern for public health due to their ubiquity as complex mixtures. Our goal was to study the effect of an EDC mixture on female sexual development during 3 generations. Female rats (F0 generation) were orally exposed to a mixture of 13 anti-androgenic and estrogenic EDCs or corn oil for 2 weeks before gestation until weaning. The mixture was composed of plasticizers, fungicides/pesticides, UV filters, parabens and acetaminophen at doses representing human exposure. Sexual development (vaginal opening, GnRH interpulse-interval, estrous cyclicity and folliculogenesis) and maternal behavior were studied from F0 to F3 generations. At PND21, mediobasal hypothalamus of the F1 and F3 were removed for gene expression, histone modifications and DNA methylation analysis of target genes. F2 and F3 females showed delayed vaginal opening, decreased percentage of regular estrous cycle, decreased GnRH interpulse interval and altered late stage folliculogenesis. F1 and F2 females showed decreased maternal licking behavior while spending more time resting alone. The phenotype was associated with transcriptional and epigenetic alterations of hypothalamic genes involved in reproductive competence and behavior like kisspeptin (Kiss1), oxytocin (Oxt), estrogen (Esr1), glutamate (Grin2d), dopamine signaling (Th) as well as glucocorticoid activity (Nr3c1 and Crh). We have found alterations in repressive (H3K27me3, H3K9me3) or active (H3K4me3, H3K9ac) histone marks concomitant with transcriptional activity. Overall, gestational and lactational exposure to an environmentally relevant EDC mixture transgenerationally affects sexual development throughout epigenetic reprogramming of the hypothalamic control of puberty. Such effects could be mediated by alterations of maternal behavior. [less ▲]

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See detailTransgenerational Effects of Exposure to an EDC Mixture on Maternal Behavior and Sexual Development
Lopez Rodriguez, David ULiege; Awylyn, Carlos Francisco; Sevrin, Elena ULiege et al

Conference (2019)

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See detailLymph/angiogenesis contributes to sex differences in lung cancer through oestrogen receptor alpha signalling
Dubois, Charline; Rocks, Natacha ULiege; Blacher, Silvia ULiege et al

in Endocrine-Related Cancer (2019), 26(2), 201-216

Oestrogen signalling pathways are emerging targets for lung cancer therapy. Unravelling the contribution of oestrogens in lung cancer development is a pre-requisite to support the development of sex-based ... [more ▼]

Oestrogen signalling pathways are emerging targets for lung cancer therapy. Unravelling the contribution of oestrogens in lung cancer development is a pre-requisite to support the development of sex-based treatments and identify patients who could potentially benefit from anti-oestrogen treatments. In this study, we highlight the contribution of lymphatic and blood endothelia in the sex-dependent modulation of lung cancer. The orthotopic graft of syngeneic lung cancer cells into immunocompetent mice showed that lung tumours grow faster in female mice than in males. Moreover, oestradiol (E2) promoted tumour development, increased lymph/angiogenesis and VEGFA and bFGF levels in lung tumours of females through an oestrogen receptor (ER) alpha-dependent pathway. Furthermore, while treatment with ERb antagonist was inefficient, ERa antagonist (MPP) and tamoxifen decreased lung tumour volumes, altered blood and lymphatic vasculature and reduced VEGFA and bFGF levels in females, but not in males. Finally, the quantification of lymphatic and blood vasculature of lung adenocarcinoma biopsies from patients aged between 35 and 55 years revealed more extensive lymphangiogenesis and angiogenesis in tumour samples issued from women than from men. In conclusion, our findings highlight an E2/ERa-dependent modulation of lymphatic and blood vascular components of lung tumour microenvironment. Our study has potential clinical implication in a personalised medicine perspective by pointing to the importance of oestrogen status or supplementation on lung cancer development that should be considered to adapt therapeutic strategies. [less ▲]

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See detailEvaluation of Z-VAD-FMK as an anti-apoptotic drug to prevent granulosa cell apoptosis and follicular death after human ovarian tissue transplantation
Fransolet, Maïté ULiege; NOEL, Laure ULiege; HENRY, Laurie ULiege et al

in Journal of Assisted Reproduction and Genetics (2019)

Purpose To evaluate the efficiency of ovarian tissue treatment with Z-VAD-FMK, a broad-spectrum caspase inhibitor, to prevent follicle loss induced by ischemia/reperfusion injury after transplantation ... [more ▼]

Purpose To evaluate the efficiency of ovarian tissue treatment with Z-VAD-FMK, a broad-spectrum caspase inhibitor, to prevent follicle loss induced by ischemia/reperfusion injury after transplantation. Methods In vitro, granulosa cells were exposed to hypoxic conditions, reproducing early ischemia after ovarian tissue trans- plantation, and treated with Z-VAD-FMK (50 μM). In vivo, cryopreserved human ovarian fragments (n = 39) were embedded in a collagen matrix containing or not Z-VAD-FMK (50 μM) and xenotransplanted on SCID mice ovaries for 3 days or 3 weeks. Results In vitro, Z-VAD-FMK maintained the metabolic activity of granulosa cells, reduced HGL5 cell death, and decreased PARP cleavage. In vivo, no improvement of follicular pool and global tissue preservation was observed with Z-VAD-FMK in ovarian tissue recovered 3-days post-grafting. Conversely, after 3 weeks of transplantation, the primary follicular density was higher in fragments treated with Z-VAD-FMK. This improvement was associated with a decreased percentage of apoptosis in the tissue. Conclusions In situ administration of Z-VAD-FMK slightly improves primary follicular preservation and reduces global apo- ptosis after 3 weeks of transplantation. Data presented herein will help to guide further researches towards a combined approach targeting multiple cell death pathways, angiogenesis stimulation, and follicular recruitment inhibition. [less ▲]

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See detailPersistent vs Transient Alteration of Folliculogenesis and Estrous Cycle After Neonatal vs Adult Exposure to Bisphenol A.
Lopez Rodriguez, David ULiege; Franssen, Delphine ULiege; Sevrin, Elena ULiege et al

in Endocrinology (2019), 160(11), 2558-2572

Exposure to bisphenol A (BPA), a ubiquitous endocrine-disrupting chemical (EDC), is known to produce variable effects on female puberty and ovulation. This variability of effects is possibly due to ... [more ▼]

Exposure to bisphenol A (BPA), a ubiquitous endocrine-disrupting chemical (EDC), is known to produce variable effects on female puberty and ovulation. This variability of effects is possibly due to differences in dose and period of exposure. Little is known about the effects of adult exposure to environmentally relevant doses of this EDC and the differences in effect after neonatal exposure. This study sought to compare the effects of neonatal vs adult exposure to a very low dose or a high dose of BPA for 2 weeks on ovulation and folliculogenesis and to explore the hypothalamic mechanisms involved in such disruption by BPA. One-day-old and 90-day-old female rats received daily subcutaneous injections of corn oil (vehicle) or BPA (25 ng/kg/d or 5 mg/kg/d) for 15 days. Neonatal exposure to both BPA doses significantly disrupted the estrous cycle and induced a decrease in primordial follicles. Effects on estrous cyclicity and folliculogenesis persisted into adulthood, consistent with a disruption of organizational mechanisms. During adult exposure, both doses caused a reversible decrease in antral follicles and corpora lutea. A reversible disruption of the estrous cycle associated with a delay and a decrease in the amplitude of the LH surge was also observed. Alterations of the hypothalamic expression of the clock gene Per1 and the reproductive peptide phoenixin indicated a disruption of the hypothalamic control of the preovulatory LH surge by BPA. [less ▲]

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