Male germ cells are susceptible to radiation-induced injury, and infertility is a common problem after total-body irradiation. Here we investigated, first, the effects of irradiation on germ cells in mouse testis and, second, the role of sphingosine-1-phosphate (S1P) treatment in radiation-induced male germ cell loss. Irradiation of mouse testes mainly damaged the early developmental stages of spermatogonia. The damage was seen by means of DNA flow cytometry 21 days after irradiation as decreasing numbers of spermatocytes and spermatids with increasing amounts of ionizing radiation (0.1–2.0 Gy). Intratesticular injections of S1P given 1–2 h before irradiation (0.5 Gy) did not protect against short-term germ cell loss as measured by in situ end labeling of DNA fragmentation 16 h after irradiation. However, after 21 days, in the S1P-treated testes, the numbers of primary spermatocytes and spermatogonia at G2 (4C peak as measured by flow cytometry) were higher at all stages of spermatogenesis compared with vehicle-treated testes, indicating protection of early spermatogonia by S1P, whereas the spermatid (1C) populations were similar. In conclusion, S1P appears to protect partially (16%–47%) testicular germ cells against radiation-induced cell death. This warrants further studies aimed at development of therapeutic agents capable of blocking sphingomyelin-induced pathways of germ cell loss.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.