Just Accepted

This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.

Spermatogenic cell apoptosis and impaired spermatogenesis in prepubertal mice: Time- and dose-dependent toxicity of silver nanoparticles

Zannatul Maowa, Md. Sharifur Rahman, M. Nazmul Hoque, Abdullah Al Mahmud, Mohammad Shah Alam

Abstract

Context: The increasing use of nanoparticles (NPs) in various consumer, agricultural, and pharmaceutical applications has raised considerable concern about their potential risks to human health and the environment. Aims: This study investigated the progressive toxic effects of silver nanoparticles (AgNPs) in mouse testes after single and repeated exposure. Methods: Prepubertal male mice were exposed to AgNPs by gavage at 50, 200, and 500 mg/kg body weight. Testis, epididymis, and serum were collected and subjected to histopathological analysis. Key results: Daily exposure to AgNPs for 7 and 15 days (n = 8) decreased sperm count while increasing abnormal sperm count and testicular atrophy in a dose- and exposure-time-dependent manner. A single exposure to AgNPs at a dose of 200 mg/kg body weight (n=8) resulted in testicular histopathological changes and spermatogenic cell apoptosis in a time-dependent manner. The highest number of apoptotic cells was detected 24 hours (h) after exposure while testicular testosterone (TT) concentrations decreased at 12 and 24 h. To explore whether AgNPs suppress TT concentrations by affecting the hypothalamus-pituitary-testicular (HPT) axis, we analyzed serum LH concentrations; however, no significant changes in LH levels were found. Conclusion: This study showed that AgNPs cause potential adverse effects on the testis, specifically, spermatogenic cell apoptosis, and impaired spermatogenesis in an exposure time- and dose-dependent manner. The testicular toxicity was not associated with suppression of the HPT axis, possibly involving other mechanisms. Implications: These findings contribute to the broader discussion on NPs safety and regulatory considerations, particularly regarding their reproductive toxicity.

RD24161  Accepted 25 March 2025

© CSIRO 2025