Biology subjects

Stapleton, P.

Publications and source records attributed to Stapleton, P..

3 recordsLinked to original sources

bioRxiv2026

Inhalation of nanoparticles during pregnancy enhances placental glucose transport in rats

Fetal health is heavily dictated by the maternal environment. Inhaling airborne pollutants, like particulate matter, is associated with pregnancy complications and fetal developmental pathologies, including fetal growth restriction (FGR). Because fetal growth is dependent on the placental transfer of nutrients from the maternal circulation, particularly glucose, investigating glucose transport capacity is critical to understanding the development of FGR associated with gestational inhalation of particulate matter. Pregnant Sprague Dawley rats were exposed to titanium dioxide nanoparticles (9.8{+/-}1.0 mg/m3) as a proxy for ultrafine particulate matter, from gestational day (GD) 5 to GD 19 via whole-body inhalation. Glucose transporters (GLUTs) 1, 3 and 4 were evaluated in term placentas on GD 20 and ex vivo placental perfusion was conducted as a functional assessment of glucose transport. Exposure resulted in a reduction in Glut3 mRNA and GLUT1 protein. However, exposed placentas exhibited an adaptation, characterized by increased GLUT4 expression and membrane localization of both GLUT1 and GLUT4. Placental perfusion confirmed these molecular changes, revealing increased glucose flux in exposed placentas compared to control (AUC 95% CI: 77.4 to 127.5 vs 39.1 to 73.6, respectively). Contrary to our hypothesis, exposure to these nanoparticles enhanced glucose transport across the placenta. Here we have demonstrated that inhaling airborne pollutants during pregnancy modulates placental function and nutrient transport mechanisms, which can have direct effects on fetal development. Furthermore, we provide evidence for targeted interventions, aimed at mitigating fetal developmental pathologies. HighlightsO_LIGestational inhalation of nanoparticles decreases GLUT1 expression in the placenta. C_LIO_LIThe placenta adapts to gestational nanoparticle inhalation by enhancing GLUT4 expression and GLUT1 and GLUT4 membrane localization. C_LIO_LIEx vivo placental perfusion demonstrated increased glucose flux across to the placenta to the fetus following gestational inhalation of nanoparticles. C_LI

pharmacology and toxicology↗

bioRxiv2026

Gestational inhalation of nanoparticles disrupts placental zone structure and induces vascular placentation in rats

Airborne contaminants represent a significant environmental health concern for vulnerable populations, including pregnant individuals. In particular, maternal inhalation of particulate matter (PM) during pregnancy has been linked to adverse outcomes such as fetal growth restriction (FGR). Increasing evidence identifies placental dysfunction as a mechanism for this condition. Placental efficiency, defined as the ratio of fetal mass to placental mass, is frequently altered in FGR. Many aspects contribute to placental efficiency including surface area available for nutrient and waste exchange and placental vascularization. In this study, we hypothesized that maternal inhalation of ultrafine PM during pregnancy would reduce the size and/or number of placental structures that are necessary for nutrient transport. Engineered titanium dioxide nanoparticles (nano-TiO2) were used as a proxy for ultrafine PM and pregnant Sprague Dawley rats were exposed via whole-body inhalation to nano-TiO2 aerosols (9.23 {+/-} 0.39 mg/m3) from gestational day (GD) 5 to 19. On GD 20, placentas were collected and processed for histological evaluation. While gestational inhalation of nano-TiO2 did not affect placental weight or efficiency, it reduced decidua and labyrinth zone size. Exposed placentas exhibited compensatory adaptations characterized by increased blood space number and maternal blood space expansion. Together, these findings indicate that inhalation of nanoparticles disrupts placental structure while simultaneously eliciting adaptive vascular responses that may preserve nutrient exchange capacity. By characterizing the effects of PM exposure on placental morphology and structure, this study highlights the placenta as a vulnerable target of inhaled pollutants and provides mechanistic insight into pathways contributing to PM-induced FGR.

pharmacology and toxicology↗

bioRxiv2026

Polystyrene Nanoplastics Disrupt Mouse Placenta Development in a Sex-Dependent Manner

Plastic production has been increasing exponentially. Throughout their lifespan, plastics degrade into smaller particles that accumulate in our bodies and the environment. Recent studies found these plastic particles can cross the placental barrier and reach the fetus. However, the impact of plastic particles on placental function is still unknown. We hypothesized that nanoplastics would disrupt placental growth and function, specifically focusing on transforming growth factor beta (TGF{beta}) signaling. To understand the impact of plastic particles on the placenta, we orally exposed pregnant CD-1 mice to 50 nm or 200 nm polystyrene plastic particles from gestation day 8 to day 15 at a human-relevant concentration of 5 mg/kg/day. After euthanization on day 15, placenta and fetus weights were recorded, and tissues were prepared for histomorphology and gene expression analysis. We observed a statistically significant decrease in the area of the decidua in the placentas for the 200 nm treatment group and a borderline significant decrease in decidua area for the 50 nm treatment group compared to control. However, when we separated by sex, only the male decidua were significantly decreased in the 200 nm group. Gene expression analysis of key signaling factors in the TGF{beta} pathway identified increased expression of Smad2 and Smad3, which may be suppressing prolactin and estrogen receptor signaling. Overall, both particle sizes disrupted placenta structure and signaling in a sex-dependent manner and may be acting as endocrine disruptors.

pharmacology and toxicology↗