Impact of Copper Oxide Nanoparticles on Adult Rat Ovary and Possible Protective Effect of Selenium: A Histological and Immunohistochemical Study

Copper oxide nanoparticles are thought to be an important transition metal oxide due to their interesting properties. Selenium is an important structural component of numerous enzymes, including glutathione peroxidase (GPx), thioredoxin reductase, as well as deiodinases.The present work was undertaken to evaluate the histological and immunohistochemical alterations in the adult rat ovary after oral administration of CuO-NPs, and to assess the potential ameliorative impact of selenium. Sixty adult female albino rats were equally divided in two major groups: group I and group II. Group I was further divided into three groups: control group IA, group IB: given 2000 mg/kg CuO-NPs once, group IC: received selenium (0.5 mg/kg), five days before giving one high dose of 2000 mg/kg CuO-NPs. Thereafter, given selenium for 14 days. group II was subdivided into three groups: group IIA (control), group IIB: received 300 mg/kg/dayof CuO-NPs for 28 days, group IIC: received selenium (0.5 mg/kg), five days before starting concomitant administration of 300 mg/kg CuO-NPs and 0.5 mg/kg selenium for 28 days. Both group IB and group IIB showed signs of follicle and corpora lutea degeneration and revealed increased numbers of apoptotic bodies and atretic follicles. Increased reactions for caspase 3 and decreased reactions for BCL2 were also demonstrated. Apoptosis was greater in group IB. Group IC and group IIC showed apparent improvement of the histological structure, decreased numbers of apoptotic bodies (by 34.3% for the acute study and 38% for the chronic study)，decreased atretic follicles (by 37.5% for the acute study and 34.78% for the chronic study), decreased reactions for caspase 3 and increased reactions for BCL2 as compared to groups IB and IIB respectively.