Changes in semen characteristics and sex hormones of rats treated with iron oxide nanoparticles, silver nanoparticles and their mixture

Few studies have demonstrated the toxicity of iron oxide nanoparticles (Fe₂O₃NPs), and silver nanoparticles (AgNPs), and their combination on reproductive performance.Therefore, the present study aimed to investigate the reproductive toxicity of iron oxide nanoparticles, silver nanoparticles and their combination in male rats. Forty Wistar male rats were divided into 4 equal groups. Group 1 served as control, group 2 was administered orally with Fe₂O₃NPs (5 mg/kg BW; >50 nm), group 3 was treated intraperitoneally with AgNPs (50 mg/kg BW; >100 nm) and group 4 was administered with the mixture of Fe₂O₃NPs with AgNPs. Animals were treated with doses every day for 79 days. The results revealed that semen parameters (sperm count, abnormal sperm and sperm motility) of adult male rats treated with Fe₂O₃NPs, AgNPs and their combination showed significant (P<0.05) reduction in sperm motility and sperm count, and significant (P<0.05) induction in abnormal sperm compared to the control group. Results also showed significant (P<0.05) decrease in the levels of testosterone and TSH, and significant (P<0.05) increase in FSH, LH, T3 and T4 levels in rats treated with Fe₂O₃NPs, AgNPs and their combination compared to the control group. The specific activity of testicular 17β-hydroxysteroid dehydrogenase (17β-HSD) was significantly decreased, while 17-ketosteroid reductase (17-KSR) was significantly increased in animals treated with Fe₂O₃NPs, AgNPs and their combination compared to the control group.  It was concluded that rats exposed to Fe₂O₃NPs, AgNPs or their combination caused testes inflammation and sex hormones imbalance that affect reproductive performance.