Protective Effect of Cast-Off Skin of Water Extract in a Radiation-Induced Testicular Injury Mice Model.

Radiation therapy has been used to treat cancer; however, the associated DNA damage and adverse effects in the surrounding tissues remain major concerns. In radiation injury, several natural remedies can effectively relieve symptoms with minimal side effects. (CP, also called "Sun-Tae") is the cast-off shell of Fabricius and has been traditionally used for several pharmacological actions. This study investigated the protective effects of CP water extract (CPE) on irradiated testicular tissue and spermatogenesis. The chemical constituents of CPE were analyzed using a high-performance liquid chromatography system equipped with a mass detector and were determined to be dimeric -acetyl dopamine derivatives. The testes and epididymal tissues of male C57BL/6 mice orally pretreated with CPE (25 and 50 mg/kg) 24 h and 15 min before radiation exposure (5 Gy) were collected for analysis. CPE pretreatment ameliorated radiation-induced apoptosis in the testes and inhibited weight loss in the epididymis compared to those of the irradiated group. Treatment with high-dose CPE prevented the radiation-induced decrease in the epithelial height of seminiferous tubules. In addition, the morphology, motility, and number of damaged sperm cells following radiation exposure were alleviated by CPE treatment. Furthermore, the dose-dependent antioxidative activity of CPE was confirmed in 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging assays, and reactive oxygen species generation by hydrogen peroxide was reduced by CPE treatment in vitro. Our findings suggest that pretreatment with CPE can ameliorate testicular tissue damage and sperm degeneration via the antioxidative properties of CPE in radiation-injured testis tissue.