Studies Of Female Reproductive Toxicity Of Three Nanoparitcles In Vitro

The dramatic expansion of the nanotechnology industry has prompted the need toinvestigate potential toxic effects of nanoparticles on human health as well as the environment. No final conclusion has been reached on whether the standardized protocols forstandard chemicals to assess the hazards of substances released into the enviro nment areappropriate for nanomaterials. Reproductive and developmental toxicity testing plays animportant role in the current safety evaluation system. Another critical challenge iswhether the current methods for reproductive and developmental toxicology could workfor nanomaterials.In-vitro rat preantral follicle three dimensional culture systems were used to determine the possible female reproductive toxic effects on female rats of three widely usednanoparticles via exa mining the follicle development, hormone production, growth ofegg, and ovulatory function. In addition, the toxic mechanism was also explored preliminarily. And hope can offer evidence and accumulate data for the female reproductivetoxicity characteristics of nanomaterials.1. Silica nanoparticles (SiO2-NPs)Objective: Study the effects of SiO2-NPs on the rat follicle development, oocytematuration and the proliferation of rat ovarian granulose cells. Methods: Preantralfollicles (140-170m) were mechanically isolated from12to14-day-old female rats,embedded with alginate gel, and cultured in96-well plate (1preantral follicle per well).The culture medium was exchanged every other day. Five groups were setup: four groupstreated with30nm SiO2-NPs (1.0g/mL,10.0g/mL,50.0g/mL, and100.0g/mL);one negative control group used medium. The follicles were induced ovulation aftersubsequently cultured for10days, and the condition of follicle development and oocytematuration were evaluated. The proliferation rate of granulose cells was analyzed byCCK-8assay. Results: Follicles in control group grew well during the continuous culture,and developed from preantral follicles, antral follicles, to mature follicles. Along with theincrease of dosage, the rates of survival, antral follicles and COCs releasing had atendency of reduction. Comparing with the concurrent negative control èthe differencesof survival rate has a statistical significance at1.0g/mL or above (p<0.05). The rates ofantral follicles and COCs releasing has a significance statistical differences at above10.0g/mL (p<0.01). However, there is no statistical difference of oocyte maturation compared with control group (p>0.05) at any dose levels. Conclusion: The proliferationof rat ovarian granulose cell can be notably habited at1.0g/mL compared withconcurrent controls (p<0.01), and the inhabitation effects on ovarian granulose cell.wasseverer than on follicles. Conclusion:30nm SiO2-NPs can affect the survival of thein-vitro rat follicle, and inhibit the development of both follicle and granulose cells.2. Zinc oxide nanoparticles ZnO-NPsObjective: Study the effects of30nm ZnO-NPs on the rat follicle development,oocyte maturation and the proliferation of rat ovarian granulose cells. Methods: Theculture system is same as mentioned above. Five groups were setup: four groups treatedwith30nm ZnO-NPs (1.0μg/mL,5.0μg/mL,25.0μg/mL, and50.0μg/mL); onenegative control group given medium. Results: Follicles in control group grew wellduring the continuous culture, and developed from preantral follicles, antral follicles, tomature follicles. Along with the increase of dosage èthe rates of survival, antral folliclesand COCs releasing had a tendency of reduction. Comparing with the concurrentnegative control èthe differences of survival rate has a statistical significance at5.0g/mL or above (p<0.05). The rates of antral follicles and COCs releasing has asignificance statistical differences above1.0g/mL (p<0.01). However, there is nodifference of the reates of oocyte maturation between the treated groups and the controlgroup (p>0.05). The proliferation of rat ovarian granulose cell can be notably habited at25.0g/mL compared with concurrent controls. All of the above toxic effects have adose-response relationship. Conclusion:30nm ZnO-NPs can affect the survival of thein-vitro rat follicle and also inhibit the development of both follicle and granulose cells.3. Sliver nanoparticles (Ag-NPs)Objective: Study the effects of Ag-NPs on the rat follicle development, oocytematuration and the proliferation of rat ovarian granulose cells. Methods: The culturesystem is same as mentioned above. Five groups were setup: four groups treated withAg-NPs (1.0μg/mL,10.0μg/mL,50.0μg/mL, and100.0μg/mL); one negative controlgroup given medium. Results: Follicles in control group grew well during the continuousculture, and developed from preantral follicles, antral follicles, to mature follicles. Alongwith the increase of dosage èthe rates of survival, antral follicles and COCs releasing hada tendency to reduce. Comparing with the concurrent negative control èthe differences ofsurvival rate has a statistical significance at50.0g/mL or above (p<0.05). The rates of antral follicles and COCs releasing has a significance statistical differences at above1.0g/mL (p<0.01). However, there is no difference of oocyte maturation betweentreated groups and the control group (p>0.05). The proliferation of rat ovarian granulosecell can be notably habited at1.0g/mL compared with concurrent controls (p<0.01).Conclusion: Ag-NPs can affect the survival of the in-vitro rat follicle, and inhibit thedevelopment of both follicle and granulose cells.Theses three nanoparticles showed remarkable toxic effects on follicles,especifically on the growth and development of follicles at the dose of1.0g/mL orabove. Antrum cavity formation is a key process for follicle maturation, and easilyinterrupted by these three nanoparticles according to our study. Effects on follicle growthand development could be observed since D6at higher dose while D10at lower dose.Ovarian granulose cell was considered as target cell for SiO2-NPs and Ag-NPs, but notfor ZnO-NPs. Mechanism of toxic on follicles were considered different for SiO2-NPsand Ag-NPs (possibly via injuring ovarian granulose cells to hurt follicles, and the effectmechanism on ovarian granulose cells could not be deter mined under this study) fromZnO-NPs (possibly direct hurt follicles); differentiation and development changes werenoted while no effects on viability for Ag-NPs observed; changes on viability wereassociated with effects on differentiation and development of follicles for SiO2-NPs andZnO-NPs.