Introduction: Silver nanomaterials; the engineered nanomaterials; have many industrial applications. They are used in manufacture of cosmetic and daily used products as food and clothes. Nanoparticles can pass through different biological body barriers, accumulate in the female reproductive organs as uterus and ovaries and exert their toxicity.
Aim of the Work: To evaluate the effect of silver nanoparticles on the histological structure of the endometrium using different histological and immunohistochemical techniques.
Materials and Methods: Thirty-six adult female albino rats were divided into three equal groups; group I (control group), group II and group III. Silver nanoparticles were administered daily for 2 weeks at dose 30mg /kg and 300mg/kg respectively orally to group II and III. The size of the used nanoparticles is 20 nm. Specimens of uterus were taken to be processed for examination by light microscope (haematoxylin and eosin, Masson trichrome and TNF- alpha immunohistochemical staining) and transmission electron microscope.
Results: AgNps-treated animals showed stratification, cytoplasmic vacuolation, discontinuation and desquamation in endometrial epithelial cells. The lamina propria showed cellular infiltration (inflammatory reaction), empty spaces and increase the deposition of collagen fibers (fibrosis). Ultrastructurally, they showed focal loss of the apical microvilli of the endometrial epithelial cells, apical cytoplasmic vacuoles, swollen, distorted and irregularly arranged mitochondria and large amount of secondary lysosomes and autophagic vacuoles. Focal separation of the epithelial cells with destruction of the intercellular junctions was seen. The lamina propria showed accumulation of collagen fibres and eosinophilic infiltration. Immunohistochemical study revealed highly significant increase in the TNF- alpha immunoexpression particularly in group III. All these changes were more severe in animals with high dose than those of low dose.
Conclusion: Silver nanoparticles induce structural changes in a dose dependent manner in the endometrium. So, it should be given cautiously to females to avoid uterine damage.