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Integration of the exposome concept into health risk assessments: a challenge for health safety agencies
No full textInternational audienceThe exposome is a concept that aims to study the environmental factors to which individuals are exposed during their lifetime and the role of these factors in the development of chronic diseases. Since the concept emerged in 2005, new data, methods, and tools have been generated by the scientific community to assess the different components of the exposome and their impacts on human health. Currently, one of the main challenges is accounting for the diversity and complexity of exposures and their effects on health in risk assessment, which might be accomplished by integrating the exposome into this process. To this end, a working group was constituted by Anses to develop a strategy to integrate the exposome concept in risk assessment and more generally in the work produced by health safety agencies. We present the principal challenges to be addressed by considering 8 themes covering relevant aspects of the exposome and we made recommendations for each theme: 1) characterization of the exposome in epidemiological surveys; 2) exposome data; 3) risk assessment of chemical mixtures; 4) aggregation of multiple sources and routes of exposure; 5) dynamics of the exposure in the context of time, space, and social factors; 6) establishment of reference values; 7) multiple factors in risk, benefit and health impact assessment; and 8) eco-exposome. Then, we propose practical recommendations with short-, medium-, and longterm time scales to progressively operationalize the exposome into risk assessments implemented by health safety agencies. We also discuss how providing broader exposome input into risk assessment can support risk regulators to incorporate exposome input into risk management
Immunometabolic reprogramming of macrophages by gut microbiota-derived cadaverine controls colon inflammation
No full textInternational audienceCadaverine is a polyamine produced by the gut microbiota with links to health and disease, notably inflammatory bowel disease (IBD). Here, we show that cadaverine shapes monocyte-macrophage immunometabolism in a context- and concentration-dependent fashion to impact macrophage functionality. At baseline, cadaverine is taken up via L-lysine transporters and activates the thioredoxin system, while during inflammation, cadaverine signals through aconitate decarboxylase 1 (Acod1)-itaconate. Both pathways induce activation of transcription factor, nuclear factor erythroid 2-related factor 2 (Nrf2), which supports mitochondrial respiration and promotes immunoregulatory macrophage polarization. Conversely, under higher concentrations, cadaverine acts via histamine 4 receptor, leading to glycolysis-driven inflammation and pro-inflammatory functions in macrophages. Likewise, cadaverine exhibits paradoxical effects in experimental colitis, either protective or detrimental, evoking opposite fates on macrophages depending on levels dictated by Enterobacteriaceae. In IBD patients, elevated cadaverine correlated with higher flare risk. Our findings implicate cadaverine as a microbiota-derived metabolite manipulating macrophage energy metabolism with consequences in intestinal inflammation and implications for IBD pathogenesis
Volatility during the Global Financial Crisis and COVID-19 pandemic through the lens of high-frequency data: a Realized GARCH approach
No full textThis article has two primary objectives: 1) to propose a new parametric model of volatility and 2) to identify the days with the most significant volatility shocks, while exploring the events that triggered these shocks. We analyze financial volatility during the global financial crisis and the COVID-19 pandemic, utilizing high-frequency financial data and an improved model, which incorporates asymmetry and handles outliers, to estimate volatility and determine the timing of the largest shocks within the day. For instance, for the global financial crisis, major volatility shocks coincide with events such as the bankruptcy of Lehman Brothers and the failure of the Emergency Economic Stabilization Act. However, the largest shock occurred on February 27, 2007, which, despite coinciding with market events like a Chinese stock market crash and Freddie Mac's tighter subprime loan policy, was primarily caused by a computer glitch. Our analysis underscores the value of high-frequency data in modeling financial volatility and identifying the key events driving volatility shocks
L'engagement des salariés dans la transition écologique : les enseignements de deux enquêtes de terrain en CHU
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Respirons One-Health: les interactions hôte mycobactéries dans le poumon ex vivo.
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Ageing-driven molecular and functional changes in the bovine endometrium
No full textInternational audienceUnderstanding how ageing impacts endometrial function is crucial for preserving fertility in older females. While ageing-related cellular dysfunction and inflammation are observed in the bovine uterus, its effects on endometrial physiology remain unclear. Using an experimental model of young (4−7 years) and old (13−15 years) cloned female cattle, we assessed the effect of ageing on the endometrium through transcriptome profiling and responses of cultured endometrial cells to interferon tau (IFNT) and of cultured endometrial explants to LPS. Progesterone profiles were similar between young and old females. Transcriptomic analysis of endometrial biopsies on day 15 of the estrous cycle identified 859 differentially expressed genes (DEG; p ≤ 0.05, |FC| ≥ 1.5), among which 402 DEG were over-expressed and 457 DEG were under-expresssed in old females. These DEG are linked to immune, inflammatory, metabolic, and cell organization pathways and networks. RT-qPCR validation of selected candidate DEG revealed an increased expression of COL4A3, CPA3, IGFBP1, IGFBP2, RSAD2, SCARA5, and SERPINA14 in young females. In vitro stimulation with IFNT of primary uterine glandular epithelial and stromal cells revealed that glandular epithelial cells exhibit a greater sensitivity to IFNT than stromal cells, both in old and young females. Glandular epithelial cells derived from old females exhibit a weaker response to IFNT, in terms of the number of differentially expressed genes, compared to those from young females. The effect of LPS treatment on cytokine concentrations was lightly more pronounced in young females than in old females, with LPS leading to a significant increase in the concentration of IL-1α, IL-1β, IL-6 and IL-10 in young females. By altering the transcriptomic profile of the endometrium and its capacity to respond to both the embryo's signal and inflammatory factors, we propose that age may be a key factor underlying uterine-related reproductive failures. Further experiments are required to confirm this hypothesis
Effets d'une induction de méditation de pleine conscience sur la mémoire et la métamémoire épisodiques dans le vieillissement normal : résultats préliminaires
No full textInternational audienceIn the context of demographic aging, it is essential to identify and understand theunderlying mechanisms of reserve factors (Stern, 2002), such as a regular mindfulnessmeditation practice (Chételat et al., 2022). However, no study has examined how a briefmindfulness induction could influence episodic memory and metamemory in older adults. So,in this study, young (N = 29) and older adults (N = 36) with no prior meditation experience,have listened either to a short mindfulness induction or a mindwandering audio beforecompleting a Feeling of Knowing (FOK) task. They also completed questionnaires measuringanxiety, mindfulness and mindwandering states variations. Results showed effects of both ageand induction group on episodic memory performance, but no on episodic metamemory. Then,follow-up analyses suggest that the observed memory benefit from mindfulness may be linkedto the increase of decentering state (a mindfulness-state subscore). Finally, no significantinteraction between age and induction condition was found, for either episodic memory andmetamemory performances. Overall, these findings suggest that a bried mindfulness inductionmay enhance episodic memory in both young and older people, while its effect on metamemorystill nedds to be clarified with futher researchs.Dans un contexte de vieillissement démographique, il est essentiel d’identifier et decomprendre les mécanismes sous-jacents des facteurs de réserve (Stern, 2002), tels qu’un hautniveau d’éducation ou une pratique régulière de méditation de pleine conscience (Chételat etal., 2022). Toutefois, aucune recherche n’avait encore exploré l’effet d’une courte induction depleine conscience sur la mémoire et la métamémoire épisodiques dans le vieillissement. Pourcela, des adultes jeunes (N = 29) et âgés (N = 36), n’ayant aucune expérience de méditation ontété invités à écouter, soit une induction de pleine conscience, soit un audio de mindwandering(ou de vagabondage de l’esprit), avant de réaliser une tâche de Feeling of Knowing (FOK). Parailleurs, ils ont également rempli divers questionnaires évaluant notamment leurs niveauxd’anxiété et de pleine conscience (ou de mindwandering) états. Les résultats ont confirmé deseffets significatifs de l’âge et de l’induction sur les performances de mémoire épisodique, maispas sur la métamémoire épisodique. Des analyses complémentaires suggèrent que cet effetbénéfique de l’induction de pleine conscience sur la mémoire pourrait être en lien avec uneaugmentation du niveau de décentrage (i.e. sous-score de pleine conscience-état). Enfin, aucuneinteraction significative entre l’âge et le groupe d’induction n’a été retrouvée sur la mémoire etla métamémoire épisodiques. Ainsi, ces résultats suggèrent que l’effet d’une induction de pleineconscience est susceptible d’améliorer les performances de mémoire épisodique chez lesadultes jeunes et âgés, mais que son effet sur la métamémoire reste à précise
Testosterone therapy is associated with reduced risk of acute kidney injury, kidney failure with renal replacement therapy, and cardiovascular events in men with diabetes and hypogonadism
No full textInternational audienceBackground: Testosterone deficiency is common in men with diabetes. Effects of testosterone therapy on kidney failure and cardiovascular outcomes in diabetic men remain poorly understood. Our aim was to assess whether testosterone therapy is associated with reduced risk of acute kidney injury and kidney failure requiring replacement therapy in men with diabetes and hypogonadism compared to matched untreated men with diabetes.Methods: Participants were recruited from the TriNetX Research Collaborative network. We identified 26,027 diabetic men with hypogonadism treated with testosterone and matched them 1:1 using propensity score matching to 26,027 untreated diabetic men with hypogonadism. Primary outcomes were acute kidney injury and kidney failure requiring replacement therapy (dialysis or transplantation). Secondary outcomes included myocardial infarction, ischemic stroke, atrial fibrillation, and all-cause mortality. Cox proportional hazard models were used over a mean follow-up of 3.3 years.Results: Men had a mean age of 58 years (SD 12), with 71% being non-Hispanic White. Testosterone-treated men had significantly lower risk of acute kidney injury (HR: 0.93 [95% CI 0.87-0.98], p = 0.01) and kidney failure with replacement therapy (HR: 0.81 [95% CI 0.72-0.92], p = 0.001) compared to untreated men. Testosterone therapy was also associated with reduced risk of myocardial infarction (HR: 0.85 [95% CI 0.78-0.93], p < 0.0001), ischemic stroke (HR: 0.88 [95% CI 0.80-0.97], p = 0.01), atrial fibrillation (HR: 0.91 [95% CI 0.85-0.98], p = 0.01), and all-cause mortality (HR: 0.85 [95% CI 0.79-0.91], p < 0.0001).Conclusions: In this large real-world cohort study, testosterone therapy in diabetic men with hypogonadism was associated with significant reductions in acute kidney injury, kidney failure requiring replacement therapy, major cardiovascular events, and total mortality. These findings suggest that testosterone therapy could be more readily considered for men with diabetes and hypogonadism as a potential intervention to prevent kidney injury
: Agriculture urbaine, alimentation durable et biodiversité
No full textInternational audienceThe development of local agriculture and local food supply chains is the objective of various procedures in France: Food sector contracts, National Food Plan (PNA), National Nutrition and Health Program (PNNS), Law on the future of agriculture, food and forestry (October 13, 2014), law on sustainable food (October 30, 2018), etc. The objective is to strengthen and improve the competitiveness of the food sector, and facilitate consumer access to healthy, safe and sustainable food. This "reterritorialization" of agriculture involves building a movement to return agriculture to the territory, emphasizing new elements: new production benchmarks, new objectives and a new link to the territory. At the same time, the preservation of biodiversity is declared a priority. The National Biodiversity Strategy (NBS) is the French political response to preserve biodiversity. To achieve the ambitions set by the Global Biodiversity Framework by 2050, it proposes 40 measures focused on four areas: reducing pressures on biodiversity, restoring degraded biodiversity wherever possible, mobilizing all stakeholders, and ensuring the means to achieve these ambitions.The Bioagri-ville 2025 conference positioned itself at the intersection of these two issues:1- Reterritorialization and food sustainability; 2- Biodiversity preservation.The aim was to examine the conditions for reconciling agriculture and biodiversity in an urban context. Indeed, in cities, agricultural activity is potentially part of the urban nature supply. This agriculture also has functions other than food, since it can constitute one of the components of Green and Blue Infrastructures (TVB) – French versions of the "Green Infrastructures" implemented by the European Commission, enshrined in the Environmental Code following the Grenelle Environment Forum. This planning tool offers local stakeholders biodiversity conservation objectives. Consisting of biodiversity reservoirs and ecological corridors, TVBs play a major role in urban environments and are central to sustainable development issues.The Bioagri-ville 2025 conference aimed to identify the constituent elements of biodiversity in urban agriculture (UA) spaces to contribute to a better understanding of the services provided by ecosystems and nature-based solutions. The selected papers provided answers to three sets of questions:- What urban agriculture for what biodiversity? What do biodiversity inventories say? What knowledge is available about the biodiversity of urban agricultural spaces? What relationships can we identify in urban spaces between agricultural production systems and biodiversity? Between agricultural and horticultural practices and biodiversity?-What is the perception of urban agriculture among city technical service managers? How are urban agricultural spaces viewed by city technical service managers? How do urban agriculture stakeholders generate and use ecological knowledge to implement their projects?-How does the city integrate these urban agriculture spaces into its project? What is the role of urban agriculture in TVBs and other ecological planning? Is urban agriculture a natural space like any other, or does it have a specific relationship with the city?The Bioagri-ville 2025 conference brought together around a hundred people involved in ecology and/or land management (researchers, engineers, technicians) from the public and private sectors. It was part of the multidisciplinary research program SERANA (Ecosystemic services of agricultural spaces in the cities of New Aquitaine) financed by the New Aquitaine Region, led by the University of Poitiers (RURALITES Laboratory and UMR EBI), in partnership with UMR LIENSS and Bordeaux Sciences Agro/IRSTEA, Grand Poitiers Urban Community, Grand Châtellerault, CNRS Loire Workshop Zone, INRAE-DYNAFOR, PROXIMITES Network and Agri-ville NetworkLe développement d’une agriculture de proximité et des circuits alimentaires locaux est l’objectif de différentes procédures en France : Contrats de filière alimentaire, Plan National de l’Alimentation (PNA), Programme National Nutrition Santé (PNNS), Loi d'avenir pour l'agriculture, l'alimentation et la forêt (13 octobre 2014), loi sur l’alimentation durable (30 octobre 2018), etc. L’objectif est de renforcer et améliorer la compétitivité de la filière alimentaire, et faciliter l’accès du consommateur à une alimentation saine, sûre et durable. Cette « reterritorialisation » de l’agriculture implique la construction d’un mouvement de retour de l’agriculture vers le territoire, en insistant sur des éléments nouveaux : de nouveaux référentiels de production, de nouveaux objectifs et un nouveau lien au territoire. Dans le même temps, la préservation de la biodiversité est proclamée prioritaire. La stratégie nationale pour la biodiversité (SNB) est la réponse politique française pour préserver la biodiversité. Pour atteindre les ambitions portées par le cadre mondial de la biodiversité d’ici 2050, elle propose 40 mesures autour de 4 axes : réduire les pressions qui s’exercent sur la biodiversité, restaurer la biodiversité dégradée partout où c’est possible, mobiliser tous les acteurs, garantir les moyens d’atteindre ces ambitions.Le colloque Bioagri-ville 2025 se positionnait à l’intersection de ces deux enjeux :1-Reterritorialisation et durabilité alimentaire ; 2-Préservation de la biodiversité.Il s’agissait de s’interroger sur les conditions de rapprochement entre l’agriculture et la biodiversité dans un contexte urbain. En effet, en ville, l’activité agricole s’inscrit potentiellement dans l’offre de nature urbaine. Aussi, cette agriculture a-t-elle d’autres fonctions que l’alimentation, puisqu’elle peut constituer une des composantes des Trames Vertes et Bleues (TVB) – déclinaisons françaises des « Greens Infrastructures » mises en place par la Commission Européenne, inscrites dans le code de l’environnement à la suite du Grenelle de l’Environnement. Cet outil d’aménagement propose aux acteurs locaux des objectifs de conservation de la biodiversité. Constituées de réservoirs de biodiversité et de corridors écologiques, les TVB ont une place majeure en milieu urbain et sont au cœur de problématiques de développement durable.Le colloque Bioagri-ville 2025 ambitionnait d'identifier les éléments constitutifs de la biodiversité des espaces d’agriculture urbaine (AU) pour participer à une meilleure connaissance des services rendus par les écosystèmes et solutions fondées sur la nature. Les communications sélectionnées ont apporté des éléments de réponse à trois séries de questions :-Quelle agriculture urbaine pour quelle biodiversité ? Que disent les inventaires de biodiversité ? Quelles connaissances sur la biodiversité des espaces agricoles en ville ? Quelles sont les relations que nous pouvons identifier dans les espaces urbains entre systèmes de production agricole et biodiversité ? Entre pratiques agricoles et horticoles et biodiversité ?-Quelle perception de cette agriculture urbaine ont les gestionnaires de services techniques des villes ? Comment sont considérés les espaces agricoles urbains par les gestionnaires des services techniques des villes ? Comment les acteurs de l’agriculture urbaine génèrent et utilisent-ils les connaissances en écologie pour mettre en place leurs projets ?-Comment la ville intègre-t-elle ces espaces d’AU dans son projet ? Quelle est la place de l’AU dans les TVB et autre planification écologique. L’AU est un espace de nature comme les autres ou a-t-elle une spécificité dans son rapport avec la ville ?Le colloque Bioagri-ville 2025 a rassemblé une centaine de personnes impliquées dans l’écologie et/ou dans la gestion des territoires (chercheur, ingénieur, technicien) des secteurs publics et privés. Il s’est inscrit dans la continuité du programme de recherche pluridisciplinaire SERANA (SERvices écosystémiques des espaces Agricoles dans les villes de la Nouvelle Aquitaine) financé par la Région Nouvelle Aquitaine, porté par l’Université de Poitiers (Laboratoire RURALITES et UMR EBI), en partenariat avec l’UMR LIENSS et Bordeaux Sciences Agro/IRSTEA, Grand Poitiers Communauté Urbaine, Grand Châtellerault, Zone Atelier Loire du CNRS, INRAE-DYNAFOR, Réseau PROXIMITES et Réseau Agri-ville► Le présent document présente en bref les étapes et les discussions qui se sont déroulées lors du colloque Bioagri-ville 2025 :1-Introduction générale2-ProgrammeLes communications - Colloque scientifique Bioagri-ville 2025 « Services écosystémiques et biodiversité des espaces agricoles dans les villes », 24-26 juin 2025 à Poitiers – sont déposées sur HAL par leurs auteurs (résumés et exposés).3-Visites de sites d’agricultures urbaines à Poitiers4-Conclusions & Perspective