Les fœtus victimes du diesel - Sciencesetavenir.fr
▻http://www.sciencesetavenir.fr/sante/20160729.OBS5538/les-f-tus-victimes-du-diesel.html?xtor=RSS-16
En utilisant le modèle du lapin, une unité de l’Inra a démonté le mécanisme de pénétration des particules fines dans le placenta des femmes enceintes. Les chercheurs expliquent ainsi comment la pollution atmosphérique induit des retards de croissance chez les nouveaux-nés.
Maternal exposure to diluted diesel engine exhaust alters placental function and induces intergenerational effects in rabbits | Particle and Fibre Toxicology | Full Text
▻http://particleandfibretoxicology.biomedcentral.com/articles/10.1186/s12989-016-0151-7
Abstract
Background
Airborne pollution is a rising concern in urban areas. Epidemiological studies in humans and animal experiments using rodent models indicate that gestational exposure to airborne pollution, in particular diesel engine exhaust (DE), reduces birth weight, but effects depend on exposure duration, gestational window and nanoparticle (NP) concentration. Our aim was to evaluate the effects of gestational exposure to diluted DE on feto-placental development in a rabbit model.
Pregnant females were exposed to diluted (1 mg/m3), filtered DE (NP diameter ≈ 69 nm) or clean air (controls) for 2 h/day, 5 days/week by nose-only exposure (total exposure: 20 days in a 31-day gestation).
Results
DE exposure induced early signs of growth retardation at mid gestation with decreased head length (p = 0.04) and umbilical pulse (p = 0.018). Near term, fetal head length (p = 0.029) and plasma insulin and IGF1 concentrations (p = 0.05 and p = 0.019) were reduced. Placental function was also affected, with reduced placental efficiency (fetal/placental weight) (p = 0.049), decreased placental blood flow (p = 0.009) and fetal vessel volume (p = 0.002). Non-aggregated and “fingerprint” NP were observed at various locations, in maternal blood space, in trophoblastic cells and in the fetal blood, demonstrating transplacental transfer. Adult female offspring were bred with control males. Although fetoplacental biometry was not affected near term, second generation fetal metabolism was modified by grand-dam exposure with decreased plasma cholesterol (p = 0.008) and increased triglyceride concentrations (p = 0.015).
Conclusions
Repeated daily gestational exposure to DE at levels close to urban pollution can affect feto-placental development in the first and second generation.