Prepubertal co-exposure to nandrolone and royal jelly alters testicular histological structure and spermatogenic dynamics in male mice: Insights from histomorphometry

Objective: Nandrolone, a synthetic anabolic steroid, is frequently used for muscle enhancement but is known to compromise male fertility, particularly when administered at supraphysiological doses. Conversely, royal jelly exhibits antioxidant activity and may exert protective effects on reproductive function. This study aimed to assess the histomorphological effects of nandrolone, royal jelly, and their concurrent administration on testicular architecture during pubertal development. Methods: Thirty-five male Syrian mice (4-5 weeks old, approximately 25 g) were randomly assigned to five groups (n=7): untreated control, sesame oil vehicle, nandrolone (10 mg/kg/week), royal jelly (500 mg/kg/day), and combined nandrolone plus royal jelly. On day 32, animals were euthanized, and testicular tissues were harvested for morphological and histological evaluation. Paraffin-embedded sections were stained with hematoxylin and eosin, and seminiferous tubule diameters were quantitatively assessed. Results: Nandrolone administration increased testicular weight and the gonadosomatic index relative to controls. Royal jelly similarly enhanced testicular metrics. However, co-treatment markedly reduced testicular weight, gonadosomatic index, and lumen diameter, while germinal epithelium thickness was increased. Conclusion: Nandrolone alone may not impair fertility during pubertal maturation, and royal jelly may enhance reproductive potential when administered prepubertally. Nonetheless, their combined administration appears to disrupt spermatogenic architecture, potentially impeding sperm transit through epithelial hyperplasia and delaying testicular maturation.