University Department of Growth and Reproduction GR-5064, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen O, Denmark.
Reprod Biol Endocrinol. 2009 Nov 19;7:130. doi: 10.1186/1477-7827-7-130.
Irradiation or chemotherapy that suspend normal spermatogenesis is commonly used to treat various cancers. Fortunately, spermatogenesis in many cases can be restored after such treatments but knowledge is limited about the re-initiation process. Earlier studies have described the cellular changes that happen during recovery from irradiation by means of histology. We have earlier generated gene expression profiles during induction of spermatogenesis in mouse postnatal developing testes and found a correlation between profiles and the expressing cell types. The aim of the present work was to utilize the link between expression profile and cell types to follow the cellular changes that occur during post-irradiation recovery of spermatogenesis in order to describe recovery by means of gene expression.
Adult mouse testes were subjected to irradiation with 1 Gy or a fractionated radiation of two times 1 Gy. Testes were sampled every third or fourth day to follow the recovery of spermatogenesis and gene expression profiles generated by means of differential display RT-PCR. In situ hybridization was in addition performed to verify cell-type specific gene expression patterns.
Irradiation of mice testis created a gap in spermatogenesis, which was initiated by loss of A1 to B-spermatogonia and lasted for approximately 10 days. Irradiation with 2 times 1 Gy showed a more pronounced effect on germ cell elimination than with 1 Gy, but spermatogenesis was in both cases completely reconstituted 42 days after irradiation. Comparison of expression profiles indicated that the cellular reconstitution appeared equivalent to what is observed during induction of normal spermatogenesis.
The data indicates that recovery of spermatogenesis can be monitored by means of gene expression, which could aid in designing radiation treatment regimes for cancer patients leading to better restoration of spermatogenesis.
为了治疗各种癌症，通常会采用放疗或化疗来抑制正常精子发生。幸运的是，这些治疗后精子发生在许多情况下可以恢复，但人们对重新启动的过程知之甚少。早期的研究已经通过组织学描述了照射后恢复过程中发生的细胞变化。我们之前在小鼠出生后发育的睾丸中诱导精子发生时生成了基因表达谱，并发现了谱与表达细胞类型之间的相关性。本研究的目的是利用表达谱与细胞类型之间的联系，来跟踪照射后精子发生恢复过程中发生的细胞变化，以便通过基因表达来描述恢复过程。
成年小鼠睾丸接受 1 Gy 或两次 1 Gy 的分次照射。每隔第三或第四天取样睾丸，以跟踪精子发生恢复情况，并通过差异显示 RT-PCR 生成基因表达谱。此外，还进行了原位杂交以验证细胞类型特异性基因表达模式。
小鼠睾丸照射造成精子发生中断，该中断始于 A1 到 B 型精原细胞的丢失，持续约 10 天。两次 1 Gy 的照射比 1 Gy 对生殖细胞消除的影响更为明显，但两种情况下的精子发生都在照射后 42 天完全重建。表达谱的比较表明，细胞重建与正常精子发生诱导时观察到的情况相当。
这些数据表明，可以通过基因表达来监测精子发生的恢复情况，这可能有助于设计针对癌症患者的放射治疗方案，以更好地恢复精子发生。
