Could plastic nanoparticles be interfering with oxygen transport in living organisms? A new study from Pusan National University reveals that polystyrene nanoplastics—commonly found in packaging—disrupt red blood cell maturation in zebrafish embryos, potentially impacting aquatic life.
Polystyrene nanoparticles are widely used in consumer products. The researchers found that nanoparticle exposure alters RBC maturation, increasing immature cells while reducing mature RBCs. The study also reveals interference with heme synthesis, a process critical for oxygen transport, emphasizing the need for further research into nanoplastics’ ecological and health effects.
This was revealed using cutting-edge single-cell RNA sequencing, researchers found that these nanoparticles alter gene expression, disrupt heme synthesis, and reduce mature RBCs, raising concerns about their ecological and health effects.
Red blood cells are essential for carrying oxygen throughout the body. In this study, zebrafish embryos exposed to polystyrene nanoparticles showed an increase in immature RBCs and a decrease in mature RBCs. This suggests that the nanoparticles disrupt normal blood cell maturation.
The research team used single-cell RNA sequencing to study changes in gene expression linked to RBC development. They found that exposure to polystyrene nanoparticles interfered with the process by which immature blood cells mature into functional RBCs. Specifically, there was an accumulation of common myeloid progenitors (CMPs), which are early-stage blood cells.
Further investigations revealed that polystyrene nanoparticles disrupt heme synthesis by down-regulating key genes, thereby reducing RBCs’ oxygen-carrying capacity. This was confirmed by mass spectrometry, which detected a significant decrease in hemin levels in exposed embryos.
The research also showed that polystyrene nanoparticles affected overall protein production in RBCs, particularly reducing the expression of rps7, a gene involved in protein synthesis. To confirm the role of rps7, the team conducted knockdown experiments, which led to facial malformations and a reduction in RBCs in zebrafish embryos. These results indicate that nanoparticles impair the protein synthesis machinery necessary for RBC development.
The study’s findings have critical environmental implications. The tested concentrations of polystyrene nanoparticles (0.1–10 µg/mL) are comparable to levels detected in natural water sources, suggesting that aquatic organisms may already be experiencing similar disruptions.
With nanoplastics already in our ecosystems, this study raises urgent questions about their broader effects on aquatic life and human health and the need for further investigation and regulation.
The research appears in the journal Zoological Research, titled “Deciphering the toxic effects of polystyrene nanoparticles on erythropoiesis at single-cell resolution.”
