Implications of lead (Pb) exposure in dysregulated spermatogenesis in sexually active individuals during adulthood is well established; however, the effect of Pb exposure on spermatogenesis in the early stages of puberty is not clear yet. Moreover, the mechanism of Pb mediated dysregulation of spermatogenesis in adults is also poorly understood. Exposure to environmental toxicants during puberty may cause serious consequences in adulthood causing developmental retardations, especially in the reproductive system. Here we investigated the effects of lead exposure on spermatogenesis at the onset of puberty and the underlying mechanisms of these effects. Male ICR mice were exposed to low (50 mg/L) and high (200 mg/L) doses of Pb through the drinking water for 90 days. At the end of this period, the blood Pb level of the low-dose and high-dose exposure groups were found 6.14 ± 0.34 μg/dL and 11.92 ± 2.92 μg/dL respectively which were in agreement with the US CDC-recommended (5 μg/dL) and Chinese CDC-recommended (10 μg/dL) reference blood Pb level for the children. Although no visible toxicity was observed in either group, Pb exposure caused considerable histopathological changes in testis and epididymis; increased sperm DNA fragmentation indices as well as disrupted sperm heads and head-neck conjunctions. Moreover, both low and high-dose Pb exposures caused aberrant expressions of several important spermatogenesis-related genes in epididymis and testis. These results suggest that although the blood Pb levels are close to the recommended-reference values, low dose Pb exposure at the onset of puberty can disrupt spermatogenesis-related gene expression and cause abnormal mouse spermatogenesis.
|Journal||Toxicology and Applied Pharmacology|
|State||Published - Apr 15 2020|
Bibliographical noteFunding Information:
The study was supported by grants from the National Natural Science Foundation of China to Professor CH. Wang (Grant No. 81773471 to CH Wang).
The study was supported by grants from the National Natural Science Foundation of China to Professor CH. Wang (Grant No. 81773471 to CH Wang).We are grateful to all members of Professor CH. Wang's laboratory of the School of Health Sciences at Wuhan University, for their generous assistance. We thank the School of Health Sciences in Wuhan University for providing comprehensive experimental services. We thank Ms. Hui Liang of the School of Basic Medical Sciences in Wuhan University, for her expert technical assistance during the use of scanning electron microscopy. Meanwhile, we thank the animal facility of the Center for animal experiment in Wuhan University for maintaining mice colony.
© 2020 Elsevier Inc.
- Reproductive toxicity
- Sperm deformity
- Spermatogenesis-related gene
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