Toxic Effects Of Ag Nps On Placental Chorionic Trophoblast Cells And Adverse Pregnancy Outcomes Associated With Exposure During Pregnancy

Objective: In recent years,the rapid development of nanotechnology and the widespread use of nanomaterials have attracted high attention to the potential health risks of nanomaterials such as silver nanoparticles.Due to the complex metabolic changes during pregnancy in mammals and the high sensitivity of developing tissues to environmental factors,the biological effects of exposure to nanomaterials during pregnancy are receiving increasing attention.Pregnancy is the most sensitive window period for humans and mammals to nanomaterials.Currently,the risk of exposure to nanomaterials during pregnancy is increasing.The placenta plays a crucial role in fetal growth and development,involving many developmental events during pregnancy,such as decidualization accompanied by embryo implantation in early pregnancy,development of the placenta in mid pregnancy,and establishment of a mother fetus relationship.The decidualization of the endometrium is crucial for subsequent placental development,as decidual cells can secrete various factors to regulate the invasion of embryonic trophoblasts.Insufficient invasion of trophoblasts can lead to pregnancy complications.However,the mechanism by which AgNPs induce abnormal placental development and function in pregnant mice,leading to fetal growth restriction,is not fully understood.Methods: Selecting water-soluble 20 nm AgNPs as the research material,using human chorionic trophoblast cells(HTR-8/SVneo)as an in vitro model,the concentration gradient of AgNPs from low to high(0.5,1,2,4 μg/m L)for in vitro exposure experiments.The apoptosis and mitochondrial autophagy induced by AgNPs were identified by detecting the changes of cell viability,cell structure and mitochondrial membrane potential;Western blot was used to detect the expression levels of estrogen-related receptor proteins and mitochondrial autophagy related proteins.Using ICR pregnant mice as in vivo exposure model,three doses of AgNPs(25,50,and 100 mg/kg BW)were administered orally to pregnant mice.Blood and related organs from pregnant mice at 18.5 days of pregnancy were collected for detection and analysis,and relevant indicators of offspring were further analyzed to evaluate the impact of AgNPs exposure during pregnancy on birth outcomes.Results:(1)The activity measurement of human chorionic trophoblast cells showed that as the concentration of nano-silver increased,the cell structure significantly changed,and the cell viability significantly decreased,inducing gradual cell apoptosis.(2)High concentration(4 μg/m L),the integrity of cell membrane was damaged,the membrane potential of mitochondria was significantly decreased,and the cytoskeleton was damaged.(3)Western blot analysis showed that the expression levels of estrogen-related receptor protein(ESRRA)and mitophagy-related protein FUNDC1 and DRP1 were significantly decreased in the high concentration group(4μg/m L)with the increase of the exposure concentration of silver nanoparticles,the expression level of Hexokinase 2(HK2)protein was decreased.(4)After exposure to high-dose AgNPs during pregnancy,abnormal changes in blood routine indicators and hormone levels were observed in pregnant mice,resulting in damage to placental structure and inducing intrauterine growth restriction in mice,leading to adverse birth outcomes such as low birth weight,high absorption fetal and stillbirth rate.Conclusion:(1)Exposure to AgNPs leads to a decrease in the activity of human chorionic trophoblast cells(HTR-8/SVneo),cell structure destruction,and induction of cell apoptosis.(2)AgNPs caused the expression levels of HTR-8/SVneo estrogen-related receptor protein(ESRRA),mitochondrial autophagy related protein(FUNDC1 and DRP1)and hexokinase 2(HK2)protein to decrease significantly.(3)Exposure to AgNPs during pregnancy can lead to adverse birth outcomes.