Does preconceptional exposure to nanoparticles interfere with fetal neurodevelopment of mouse offspring?

Introduction
There is increasing understanding that exposures prior to pregnancy might interfere with fetal development. For particles, this could potentially occur if particles deposited in the lung or translocated systemically might serve as a reservoir, even after termination of exposure. Particles present in the uterus would for example be present in the tissues in which the early embryo implants. To investigate the potential developmental toxicity of preconception exposure to particles in a proof-of-principle study, we intratracheally stilled naïve, mature female mice with 100 µg of carbon black Printex 90 nanoparticles. After one month, the female cohabited with a naïve, mature male mouse to achieve pregnancy. Females carried pregnancy to term, gave birth, and took care of their young during lactation. Time-to-litter and litter parameters were registered. The central nervous system has previously shown sensitive to developmental exposure to carbon black, therefore one male and one female offspring/litter were weaned and assessed for behaviour (open field, social behavior, acoustic startle response). Brains were dissected for histological analysis of glial fibrillary acidic protein expression in 3D images in hippocampus (via optical tissue clearing), and for parvalbumin-positive interneurons and their expression of parvalbumin in the prefrontal cortex.
Results
There was no signs of effect on litter size, implantation loss, ratio of males to females nor body weight of the offspring at birth. The remaining outcomes are undergoing analasys and will be presented at the conference.
Conclusions
If exposure to carbon black prior to pregnancy interferes with fetal development, it might not suffice to terminate exposure prior to pregnancy to prevent developmental toxicity.
Summary
Exposures prior to pregnancy might interfere with fetal development. To investigate this, female mice were exposed to carbon nanoparticles one month prior to mating. Gestational parameters were unaffected; indicators of developmental neurotoxicity (behaviour, histology) will be presented.