Effect of dexrazoxane on doxorubicin-induced testicular toxicity.

Abstract

2556 Background: Seminal advances in anti-cancer therapy result in growing numbers of young male cancer survivors for whom treatment-induced infertility represents a major late-term concern. Doxorubicin (DXR) has been previously shown to exert toxic effect on the testicular germinal epithelium. Based upon the cardioprotective traits of dexrazoxane (DEX), we aimed to study its potential effect to reduce DXR-induced testicular toxicity. Methods: Male mice were injected intraperitoneally with 5mg/kg DXR or 100mg/kg DEX or the combination of both and scarified at one month post treatment. Saline-injected mice served as controls. Testes were excised, weighed and further processed. For oxidative stress determination glutathione assay was performed on testes' lysates and P38 protein levels were determined by western blot analysis. Bax levels were used to assess apoptosis. Immunohistochemistry and confocal microscopy were used to study the effect of DXR, DEX and their combination, on the testis histology as well as on the spermatogonial reserve. Results: One month after DEX and DXR treatment, a striking decline in testicular weight was observed (decrease by 60% compared with control values; decrease of 54% in DXR-only treated mice; p<0.05). DEX prevented DXR-induced oxidative stress. However, DEX enhanced DXR-induced apoptosis within the testes and furthermore, the combination depleted the spermatogonial reserve one month after treatment. Conclusions: DEX activity in the testis may differ from its activity in cardiomyocytes. Adding DEX to DXR may exacerbate DXR-induced testicular toxicity.