Exposure to airborne nanoparticles during pregnancy: lessons from rabbit models
Résumé
Background/Aims: Particles in the nm size (nanoparticles, NP, or ultrafine particles) are ubiquitous in our environment through air pollution. Feto-placental NP distribution and physiopathological consequences of maternal inhalation of pure or complex NP mixtures have been poorly explored.
Method: Pregnant rabbit females were exposed to diluted diesel exhaust (DE), a major component of airborne pollution in large European towns, at levels close to human exposure, with a mean NP size of 69nm. Exposure was performed over two hours, 5 days a week, throughout gestation. Feto-placental and postnatal effects over two generations were explored. In a second experiment, pregnant rabbits inhaled 11.5nm uncoated gold NP (Au-NP) at 132+/-38μg/m3 in the same exposure conditions. Effects on fetal phenotype and placental function were analysed.
Results: DE affected placental function and were transferred to the fetal circulation but only minor signs of fetal growth retardation were observed. Nevertheless, exposure affected placental perfusion, offspring brain function and metabolism with differences related to sex, as well as 2nd generation placental function. Exposure to Au-NP did not affect fetal growth but affected maternal erythrocyte volume and induced sex-specific alterations in placental gene expression as well as DNA lesions in maternal bone marrow and fetal kidneys of males.
Conclusions: Airborne exposure to NP can affect maternal health but also placental function and post-natal metabolic and neuronal development without directly disturbing fetal growth in rabbits.