Titanium Dioxide Nanoparticles: Effects on Development and Male Reproductive System.

Area of Science:

• Environmental Toxicology
• Nanotechnology
• Reproductive Biology

Background:

• Titanium dioxide nanoparticles (TiO2-NPs) are widely used due to their small size, leading to increased absorption by living organisms.
• These nanoparticles can distribute to various organs, including reproductive systems, raising concerns about potential toxicity.
• The zebrafish (Danio rerio) is a suitable model organism for studying the effects of nanoparticles on development and reproduction.

Purpose of the Study:

• To evaluate the toxic effects of TiO2-NPs on embryonic development in zebrafish.
• To investigate the impact of TiO2-NPs on the male reproductive system of zebrafish.
• To explore the potential endocrine-disrupting activity of TiO2-NPs.

Main Methods:

• Zebrafish embryos and adult males were exposed to TiO2-NPs at concentrations of 1 mg/L, 2 mg/L, and 4 mg/L.
• Embryonic development was monitored for interference.
• Male reproductive organs were analyzed for morphological/structural changes using immunofluorescence and qRT-PCR to assess oxidative stress, SHBG, and androgen-related gene expression.

Main Results:

• TiO2-NPs did not significantly interfere with zebrafish embryonic development.
• Exposure to TiO2-NPs caused morphological and structural alterations in male gonads.
• Biomarkers for oxidative stress and sex hormone-binding globulin (SHBG) were positive, and gene expression related to testosterone conversion increased, suggesting endocrine disruption and androgenic activity.

Conclusions:

• TiO2-NPs do not appear to affect zebrafish embryonic development.
• TiO2-NPs exhibit toxicity towards the male reproductive system in zebrafish, inducing oxidative stress and altering reproductive hormone pathways.
• The findings suggest that TiO2-NPs may act as endocrine disruptors with androgenic activity, posing a risk to male reproductive health.