Low-Dose-Rate Radiation-Induced Mouse Testicular Fibrosis

Ionizing radiation is a potent environmental stressor capable of generating excessive reactive oxygen species (ROS), leading to oxidative damage in various tissues, including reproductive organs. Despite growing awareness of oxidative stress in reproductive failure, the long-term effects of low-dose-rate (LDR) radiation on testicular function and redox imbalance remain underexplored. This study investigated the effect of prolonged LDR radiation exposure (0.39, 1.29, and 3.46 mGy/h) on mice's testicular histology and oxidative status. Although no significant differences in testis weight were observed, histological analysis revealed basal membrane disruption and reduced spermatogenic cell populations in irradiated groups. Masson's Trichrome and Sirius Red staining demonstrated dose-dependent collagen accumulation, indicating progressive testicular fibrosis. TUNEL assays confirmed increased germ cell apoptosis, while oxidative stress levels were significantly increased in the highest dose group (3.46 mGy/h). Our findings suggest that chronic LDR radiation induces testicular injury through ROS overproduction, triggering apoptosis and extracellular matrix remodeling.