Jean-Baptiste Fini

Muséum National d'Histoire Naturelle (MNHN) Paris France · AVIV (Adaptation du Vivant)

Human biomonitoring (HBM) studies have highlighted widespread daily exposure to environmental chemicals. Some of these are suspected to contribute to adverse health outcomes such as reproductive, neurological, and metabolic disorders, among other developmental and chronic impairments. One of the objectives of the H2020 European Human Biomonitoring...

Neural stem cells in the murine subventricular zone (SVZ) reactivate during postnatal development to generate neurons and glia throughout adulthood. We previously demonstrated that a postnatal thyroid hormone (TH) peak orchestrates this remodelling, rendering this process vulnerable to endocrine disruption. We exposed mice to 2 or 200 µg/kg bw/day...

Thyroid hormones (TH) are essential for normal brain development, influencing neural cell differentiation, migration, and synaptogenesis. Multiple endocrine-disrupting chemicals (EDCs) are found in the environment, raising concern for their potential effects on TH signaling and the consequences on neurodevelopment and behavior. While most research...

Severe hypothyroidism has been reported in humans during resorcinol therapeutic use. However, available data highlight differences in the severity of resorcinol-induced thyroid effects between humans and rodents, leading to a debate on the relevance of human data for its classification as a thyroid disruptor. The aim of this review is to illustrate...

Thyroid hormones (THs) are essential for normal brain development, influencing neural cell differentiation, migration, and synaptogenesis. Multiple endocrine-disrupting chemicals (EDCs) are found in the environment, raising concern for their potential effects on thyroid hormone signaling and the consequences on neurodevelopment and behavior. While...

Résumé Objectif Nous avons testé l’hypothèse qu’une carence moyenne en iode pendant la gestation, encore fréquente, malgré des apports systématiques via le sel depuis les années 70, pourrait aggraver l’action de perturbateurs endocriniens (PE) de la fonction des hormones thyroïdiennes (HTs). Le rationnel étant que les PE peuvent interagir avec le...

Background Pyrethroid metabolites are widely detectable in urine from the general population, including pregnant women and children. Pyrethroids are neurotoxic and suggested endocrine disruptors. Exposure during vulnerable developmental time windows may have long-term impacts on neurodevelopment. Objective To evaluate the epidemiological evidence...

Introduction The extensive use of the insecticide chlorpyrifos (CPF) throughout the world has brought increased scrutiny on its environmental and health impact. CPF is a cholinergic neurotoxicant, however exposure to low noncholinergic doses is associated with numerous neurodevelopmental effects in animal models. In this study, we aimed to assess C...

Background Considering non-classical environmental risk factors for osteoarthritis (OA), a systematic literature review (SLR) was performed to summarise existing knowledge on associations between OA and pollutants. Methods PubMed was used to identify studies reporting data on OA and pollutants in humans (examples of MeSH terms: “Pesticides” or “Po...

Convergent evidence associates exposure to endocrine disrupting chemicals (EDCs) with major human diseases, even at regulation-compliant concentrations. This might be because humans are exposed to EDC mixtures, whereas chemical regulation is based on a risk assessment of individual compounds. Here, we developed a mixture-centered risk assessment st...

Animals must partition limited resources between their own growth and subsequent reproduction. Endocrine disruptors (ED) may cause maternal metabolic disorders that decrease successful reproduction and might be responsible for multi- and transgenerational effects in amphibians. We found that the frog Silurana (Xenopus) tropicalis, exposed to enviro...

L’incidence des maladies non transmissibles (eg sléroses en plaques) et d’hypothyroïdies congénitales en France ont augmenté significativement depuis 30 ans (Barry et al., 2016). Étant connu le rôle essentiel de l’iode et des hormones thyroïdiennes (HT) dans le développement normal du cerveau des mammifères, une hypothèse plausible est qu’un contac...

WHAT ABOUT THE EFFECTS OF ENDOCRINE DISRUPTORS ON NEURODEVELOPMENT? Development of the central nervous system (CNS) relies on many endogenous factors. Thyroid hormones and sex steroid hormones are among the most studied endocrine systems for their regulation of neural functions, since early embryonic stages of development. Environmental exposure to...

Urp1 and Urp2 are two neuropeptides of the urotensin II family identified in teleost fish and mainly expressed in cerebrospinal fluid (CSF)-contacting neurons. It has been recently proposed that Urp1 and Urp2 are required for correct axis formation and maintenance. Their action is thought to be mediated by the receptor Uts2r3, which is specifically...

North-Eastern Brazil saw intensive application of the insecticide pyriproxyfen (PPF) during the microcephaly outbreak caused by the Zika virus (ZIKV). ZIKV requires the neural RNA-binding protein Musashi-1 to replicate. Thyroid hormone (TH) represses MSI1. PPF is a suspected TH disruptor. We hypothesized that co-exposure to the main metabolite of P...

"Le valproate de sodium". Avis de l'Anses.

Humans are simultaneously exposed to complex mixtures of chemicals with limited knowledge on potential health effects, therefore improved tools for assessing these mixtures are needed. As part of the Human Biomonitoring for Europe (HBM4EU) Project, we aimed to examine the combined biological activity of chemical mixtures extracted from human placen...

Significance Many environmental pollutants act as endocrine disruptors that interfere with normal endocrine regulation and promote adverse effects in humans. As a major target of xenobiotics, the pregnane X receptor (PXR) is known to play opposite roles by both facilitating their clearance and mediating their toxic effects. Here, we use structural...

North-Eastern Brazil saw intensive application of the insecticide pyriproxyfen (PPF) during the microcephaly outbreak caused by Zika virus (ZIKV). ZIKV requires the neural RNA-binding protein Musashi-1 to replicate. TH represses MSI1 . Being a suspected TH disruptor, we hypothesized that co-exposure to the main metabolite of PPF, 4’-OH-PPF, would e...

Human biomonitoring (HBM) studies have demonstrated widespread and daily exposure to bisphenol A (BPA). Moreover, BPA structural analogues (e.g. BPS, BPF, BPAF), used as BPA replacements, are being increasingly detected in human biological matrices. BPA and some of its analogues are classified as endocrine disruptors suspected of contributing to ad...

Metabolic disorders induced by endocrine disruptors (ED) may contribute to amphibian population declines but no transgenerational studies have evaluated this hypothesis. Here we show that Xenopus tropicalis, exposed from the tadpole stage, to the ED benzo[a]pyrene (BaP, 50 ng.L⁻¹) produced F2 progeny with delayed metamorphosis and sexual maturity....

While road network expansion is crucial for economic development, it can cause a notable disturbance of fauna, especially in protected area in terms of habitat fragmentation, risk of collision, and also indirect threat such as pollution. In this study, we monitored the 4.6-km long tarmac road crossing the Kibale National Park in Uganda, home to a r...

The test methods that currently exist for the identification of thyroid hormone system-disrupting chemicals are woefully inadequate. There are currently no internationally validated in vitro assays, and test methods that can capture the consequences of diminished or enhanced thyroid hormone action on the developing brain are missing entirely. These...

Food packaging is of high societal value because it conserves and protects food, makes food transportable and conveys information to consumers. It is also relevant for marketing, which is of economic significance. Other types of food contact articles, such as storage containers, processing equipment and filling lines, are also important for food pr...

Thyroid hormones (THs) play critical roles in profound changes in many vertebrates, notably in mammalian neurodevelopment, although the precise molecular mechanisms of these fundamental biological processes are still being unravelled. Environmental and health concerns prompted the development of chemical safety testing and, in the context of endocr...

Plant Protection Products, more commonly referred to as pesticides and biocides, are used to control a wide range of yield-reducing pests including insects, fungi, nematodes, and weeds. Concern has been raised that some pesticides may act as endocrine disrupting chemicals (EDCs) with the potential to interfere with the hormone systems of non-target...

An increase in the prevalence of many diseases affecting the nervous system in both children and adults has been reported. Some of these diseases are related to endocrine dysfunction, notably of the thyroid axis. Examples in children are attention deficit/hyperactivity disorders and Autism Spectrum Disorders, diagnosed but most often affecting the...

Background Prevalence of knee osteoarthritis (OA) has doubled since the mid-20th century. Interestingly, this increase cannot be explained solely by longer life expectancy and the obesity epidemics (1). Therefore, other environmental factors known to have increased in the recent years could be part of the explanation. Objectives We performed a sys...

Pesticides are used worldwide with potential harmful effects on both fauna and flora. The Kibale National Park in Uganda, a site renowned for its biodiversity is surrounded by tea, banana and eucalyptus plantations as well as maize fields and small farms. We previously showed presence of phytochemicals with potential endocrine disruptive effects in...

Accessibility and imaging of cell compartments in big specimens are crucial for cellular biological research but also a matter of contention. Confocal imaging and tissue clearing on whole organs allow for 3D imaging of cellular structures after being subjected to in-toto immunohistochemistry. Lately, the passive CLARITY technique (PACT) has been ad...

Endocrine-disrupting chemicals (EDCs), found in all categories of chemicals, are suspected to be a cause of declining well-being and human health, both as single molecules and as mixtures. It is therefore necessary to develop high throughput methods to assess the endocrine-disrupting potential of multiple chemicals currently on the market that are...

Epidemiological and experimental studies have raised questions as to whether the insecticide pyriproxyfen (PPF) could be implicated in the increased incidence of microcephaly associated with ZIKA infection during pregnancy. This pesticide is documented as a thyroid hormone (TH) disrupting chemical. We investigated whether environmentally relevant a...

Using in vivo animal model systems for chemical screening can permit evaluation of the signaling pathways implicated. Xenopus laevis is an ideal model organism to test thyroid axis disruption as thyroid hormones are highly conserved across vertebrates. Here, we describe a high-throughput assay using non-feeding embryonic stage transgenic X. laevis...

This review covers recent findings on the main categories of thyroid hormone disrupting chemicals and their effects on brain development. We draw mostly on epidemiological and experimental data published in the last decade. For each chemical class considered, we deal with not only the thyroid hormone disrupting effects but also briefly mention the...

Reference genes are essential for gene expression analysis when using real-time quantitative PCR (RT-qPCR). Xenopus laevis is a popular amphibian model for studying vertebrate embryogenesis and development. Further, X. laevis is ideal for studying thyroid signaling due to its thyroid dependent metamorphosis, a stage comparable to birth in humans. W...

Prenatal exposure to environmental endocrine disruptors can affect development and induce irreversible abnormalities in both humans and wildlife. The northern part of Kibale National Park, a mid-altitude rainforest in western Uganda, is largely surrounded by industrial tea plantations and wildlife using this area (Sebitoli) must cope with proximity...

Convergent evidence associates endocrine disrupting chemicals (EDCs) with major, increasingly-prevalent human disorders. Regulation requires elucidation of EDC-triggered molecular events causally linked to adverse health outcomes, but two factors limit their identification. First, experiments frequently use individual chemicals, whereas real life e...

Background: In multiple sclerosis, development of screening tools for remyelination-promoting molecules is timely. Objective: A Xenopus transgenic line allowing conditional ablation of myelinating oligodendrocytes has been adapted for in vivo screening of remyelination-favoring molecules. Methods: In this transgenic, the green fluorescent prot...

Background Socioeconomic analysis is currently used in the Europe Union as part of the regulatory process in Regulation Registration, Evaluation and Authorisation of Chemicals (REACH), with the aim of assessing and managing risks from dangerous chemicals. The political impact of the socio-economic analysis is potentially high in the authorisation a...

Xenopus is an excellent model for studying thyroid hormone signalling as it undergoes thyroid hormone-dependent metamorphosis. Despite the fact that receptors and deiodinases have been described in Xenopus, membrane transporters for these hormones are yet to be characterised. We cloned Xenopus monocarboxylate transporter 8 (mct8) and organic anion...

Thyroid hormones are essential for normal brain development in vertebrates. In humans, abnormal maternal thyroid hormone levels during early pregnancy are associated with decreased offspring IQ and modified brain structure. As numerous environmental chemicals disrupt thyroid hormone signalling, we questioned whether exposure to ubiquitous chemicals...

Thyroid hormones modulate not only multiple functions in vertebrates (energy metabolism, central nervous system function, seasonal changes in physiology and behavior), but also in some non-vertebrates where they control critical post-embryonic developmental transitions such as metamorphosis. Despite their obvious biological importance, the thyroid...

Classically, thyroid hormones (THs) have been primarily associated with postembryonic development (Tata, 1968), notably metamorphosis in anuran amphibians and flat fish. This period is parallel to the perinatal period in man and many marked developmental transitions in other species. As amply described in other chapters, metamorphosis is characteri...