Mise en place de systèmes biologiques pour la détection de perturbateurs endocriniens oestrogéniques présents dans les eaux environnementales

MONTPELLIER-BU Médecine UPM (341722108) / SudocPARIS-BIUP (751062107) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF

The chick embryo: an animal model for detection of the effects of hormonal compounds

International audienceHormonal compounds are a class of pharmaceutical product that disrupt the endocrine system of animals and humans. Exposure to these molecules, even at low concentrations, can have severely damaging effects on the environment, to organisms, and to humans. The cumulative presence of these compounds is also characterized by synergistic effects which are difficult to estimate. They are an underestimated danger to the environment and to the human population. This paper presents an in-vivo model enabling to assessment of the real impact of exposure to hormonal compounds and the synergistic effect which can be involved. The anatomical effects of in-ovo exposure to two natural estrogen compounds (estrone and estriol, at 600 ng g−1) and a synthetic estrogen (ethynylestradiol, at 20 ng g−1) have been investigated. Estrone and estriol lead to morphological defects, mainly in the urogenital system of the developing chick embryo, whereas ethynylestradiol has fewer effects. Estriol caused persistence of Müllerian ducts in 50% of male embryos and hypertrophic oviducts in 71% of females. Estrone had the same effects but at the percentages were lower. Kidney dysfunction was also observed, but only with estrone, in both males and females. We also tested estrogenic compounds in two types of cell line which are estrogen sensitive (BG1 and MCF7) then completed and confirmed our previous in-vivo results. Seven pharmaceutical-like compounds—estrone (E1), estradiol (E2), estriol (E3), ethynylestradiol (EE2), carbamazepine (C), genistein (G), and bisphenol-A (BPA)—were tested alone or in mixtures. Different effects on the two cell lines were observed, indicating that endocrine compounds can act differently on this organism. Experiments also showed that these molecules have synergistic action and induce more severe effects when they are in mixture

Gastrointestinal defects of the Gas1 mutant involve dysregulated Hedgehog and Ret signaling

Summary The gastrointestinal (GI) tract defines the digestive system and is composed of the stomach, intestine and colon. Among the major cell types lining radially along the GI tract are the epithelium, mucosa, smooth muscles and enteric neurons. The Hedgehog (Hh) pathway has been implicated in directing various aspects of the developing GI tract, notably the mucosa and smooth muscle growth, and enteric neuron patterning, while the Ret signaling pathway is selectively required for enteric neuron migration, proliferation, and differentiation. The growth arrest specific gene 1 (Gas1) encodes a GPI-anchored membrane protein known to bind to Sonic Hh (Shh), Indian Hh (Ihh), and Ret. However, its role in the GI tract has not been examined. Here we show that the Gas1 mutant GI tract, compared to the control, is shorter, has thinner smooth muscles, and contains more enteric progenitors that are abnormally distributed. These phenotypes are similar to those of the Shh mutant, supporting that Gas1 mediates most of the Shh activity in the GI tract. Because Gas1 has been shown to inhibit Ret signaling elicited by Glial cell line-derived neurotrophic factor (Gdnf), we explored whether Gas1 mutant enteric neurons displayed any alteration of Ret signaling levels. Indeed, isolated mutant enteric progenitors not only showed increased levels of phospho-Ret and its downstream effectors, phospho-Akt and phospho-Erk, but also displayed altered responses to Gdnf and Shh. We therefore conclude that phenotypes observed in the Gas1 mutant are due to a combination of reduced Hh signaling and increased Ret signaling

Systèmes de Biodétection de perturbateurs endocriniens de type oestrogéniques

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Action of Endocrine Disruptors in Urogenital Development in Chicken Embryo

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Telephones in public health policy processes in sub-Saharan Africa: a scoping review

International audienc

Action of Endocrine Disruptors in Urogenital Development in Chicken Embryo

International audienc

Systèmes de Biodétection de perturbateurs endocriniens de type oestrogéniques

International audienc

Pertinence d’une plateforme technologique de participation citoyenne pour consolider les systèmes de santé subsahariens

Introduction: A citizen participation intervention using a tollfreenumber combined with an interactive voice server to collectcitizens’ opinions on their health systems was conducted inBurkina Faso, Benin, and the Democratic Republic of Congobetween 2020 and 2021.Purpose of research: This paper aims to assess the effectiveness,sustainability, and transferability of this m-participationintervention to the health systems strengthening.Results: The analysis shows the relevance of the telephone toinclude citizens in the governance of sub-Saharan health systems.Conclusion: Information and communication technologies arean important support in the quest for better health democracy insub-Saharan Africa.Introduction : Une intervention de participation citoyenne par téléphone, via un numéro vert combiné à un serveur vocal interactif pour recueillir les opinions des citoyens sur leurs systèmes de santé a été déployée au Burkina Faso, au Bénin et en République démocratique du Congo entre 2020 et 2021. But de l’étude : Cet article évalue l’efficacité, la viabilité et la transférabilité de cette intervention participative pour consolider les systèmes de santé. Résultats : L’analyse montre une pertinence du téléphone pour impliquer les citoyens dans la gouvernance des systèmes de santé subsahariens. Conclusion : Les technologies de l’information et de la communication sont un soutien important dans la quête d’une meilleure démocratie sanitaire en Afrique subsaharienne

Environmental concentration of nonylphenol alters the development of urogenital and visceral organs in avian model.

International audienceNonylphenol (NP) is an endocrine disruptor with harmful effects including feminization and carcinogenesis on various organisms. This substance is a degradation product of nonylphenol ethoxylates (NPEO) that is used in several industrial and agricultural processes. In this paper, we examined the assessment of NP exposure on chick embryo development, using a concentration consistent with the environmental concentrations of NP. With this aim, NP (between 0.1 and 50μg/egg) was injected into the yolk of egg through a small needle hole in the shell. We report the effect of NP on chick reproductive system development although the effect we observed is lower than those observed by exposition to other endocrine disruptors. However, histological analysis highlighted a decrease of intraluminal seminiferous surface area in 64.12% of case (P = 0.0086) and an heterogeneous organization of the renal tubules when 10 μg/egg were injected. Moreover, an impairment of liver development with an abnormal bile spillage was observed when higher concentration of NP was injected (50 μg/egg)