Changes in some parameters of the reproductive system of male rats following lead exposure and the effect of bioprophylaxis

Introduction. Current challenges in toxicology include the development and modernization of biological prevention strategies to reduce the risks of long-term toxic effects of lead.

The aim of this study was to determine changes in certain biochemical and histomorphological parameters of the reproductive system of male rats following subchronic exposure to lead acetate and to establish efficacy of a bioprophylactic complex (hereinafter referred to as BPC) specially developed to reduce the severity of toxic effects.

Material and methods. The experiment was conducted on albino outbred male rats aged from 4 to 6 months. The administration was carried out orally, daily for 45 days. The dose of lead acetate was 819 mg/L. Some of the animals received a vitamin and mineral complex, the composition of which was selected based on the mechanisms of lead toxicity. The effectiveness of BPC and the toxic effects of lead acetate were evaluated 21 days after the end of the exposure.

Results. According to the obtained data, lead exposure resulted in a significant decrease in the lumen of the seminiferous tubules and an increase in the proportion of Sertoli cells with degenerative and dystrophic changes. A significantly higher number of abnormal spermatozoa in testicular smears was detected in rats treated with lead acetate compared with control. An increase in the activity of the enzyme 3β-hydroxysteroid dehydrogenase was observed in exposed rats compared to controls.

Although this study did not measure sex hormone levels in the blood of laboratory animals, we believe that the observed increase in HSD3b1 is more likely a consequence of compensatory responses to the destruction and/or dysfunction of cells responsible for androgen synthesis than a direct consequence of lead toxicity.

Limitations. We did not assess sex hormone levels or the activity of the HSD3b2 isoform of the 3bHSD enzyme.

Conclusion. Male rats exposed to lead acetate showed a slight increase in the activity of 3β-hydroxysteroid dehydrogenase, an enzyme that plays an important role in regulating sex hormone synthesis and delta-ALA metabolism. The observed histomorphometric changes included a decrease in the lumen of the seminiferous tubules, an increase in the number of abnormal Sertoli cells and degenerated spermatozoa. Our findings prove the protective potential of biological prevention strategies but highlight the importance of further profound studies of the mechanisms of lead toxicity on the male reproductive system and the effects of BPC.

Compliance with ethical standards. The study was approved by the local Bioethics Committee of the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection of Industrial Workers of Rospotrebnadzor (protocol 1A of February 3, 2025) and conducted in compliance with the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS No. 123) and Directive 2010/63/EC of the European Parliament and of the Council of September 22, 2010 on the protection of animals used for scientific purposes.

Authors’ contribution:
Nikogosyan K.M. – data collection and processing, writing, editing of the article;
Sutunkova M.P. – study design and editing;
Minigalieva I.A. – study conception and editing;
Gertan N.A. – data collection and processing;
Petrunina E.M., Sakhautdinova R.R. – data collection.
All co-authors approved the final version of the article and are responsible for the integrity of all its parts.

Conflict of interest. The authors declare the absence of obvious and potential conflicts of interest in connection with the publication of this article.

Funding. The study had no sponsorship.

Received: March 11, 2026 / Accepted: March 27, 2026 / Published: April 30, 2026

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