Nanosilica-induced Placental Inflammation and Pregnancy Complications: Different Roles of the Inflammasome Components NLRP3 and ASC

Despite the increasing commercial use of nanoparticles, little is known about their effects on placental inflammation and pregnancy complications. In this study, nanosilica (NS) particles upregulated the inflammasome component nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) and induced placental inflammation and reactive oxygen species (ROS) generation, resulting in pregnancy complications. Furthermore, NS-induced pregnancy complications were markedly improved in Nlrp3(-/-) mice but not in component apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC)-deficient (Asc(-/-)) mice, indicating the independence of NLRP3 inflammasomes. Pregnancy complications in Nlrp3(-/-) and Asc(-/-) mice phenotypes were dependent on the balance between interleukin (IL)-1α and IL-10. NS-induced pregnancy complications were completely prevented by either inhibition of ROS generation or forced expression of IL-10. Our findings provide important information about NS-induced placental inflammation and pregnancy complications and the novel pathophysiological roles of NLRP3 and ASC in pregnancy.