Low-dose radiation-induced risk in spermatogenesis

Abstract

Purpose: To discuss low-dose radiation-induced risks to male fertility focusing on potential mechanisms of low-dose radiation-induced damage on spermatogenesis, epidemiological studies of environmental radiation effects on sperm parameters and transgenerational effects following exposure of spermatogonial stem cells (SSCs).

Background: Spermatogenesis produces mature male gametes, spermatozoa, which fertilize their counterpart female gametes, oocytes. The robust maintenance system of spermatogenesis is essential for genomic conservation; however, male fertility can be readily impacted by exposure to environmental, chemical and physical factors including ionizing radiation. The mammalian testes are known to be radiosensitive yet the underlying molecular mechanisms of low-dose radiation-induced risks for spermatogenesis remain unclear. Furthermore, evidence characterizing transgenerational effects following exposure of SSCs remain controversial.

Conclusions: Current concerns over the possible effects of low-dose radiation exposure on spermatogenesis requires further elucidation that may be resolved comparing and integrating observed experimental and epidemiological data.

Keywords:

• Chernobyl nuclear accident
• Fukushima nuclear accident
• low-dose radiation-induced risk
• spermatogenesis
• transgenerational effect

Acknowledgements

This work was supported by Nakayama Foundation for Human Science, Yokohama City University Gushinkai Alumni Association, Marubun Research Promotion Foundation. The funding organizations had no role in the design and conduct of the study; in the collection, management, analysis, and interpretation of the data; or in the preparation, review, or approval of the manuscript.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Notes on contributors

Hisanori Fukunaga is a PhD student at the Centre for Cancer Research and Cell Biology, Queen?s University Belfast, Belfast, UK. After the 2011 Fukushima nuclear accident, he worked as a physician at Soma General Hospital, Soma, Fukushima, Japan. His research interests are in radiation-induced transgenerational effects on male germ stem cells.

Karl T. Butterworth is a Lecturer in Translation Radiation Biology at the Centre for Cancer Research and Cell Biology, Queen?s University Belfast, Belfast, UK. His research interests are in mechanisms of radioresistance for biologically optimization in radiotherapy and precision cancer medicine.

Akinari Yokoya is a Senior Principal Researcher at the Tokai Quantum Beam Science Center, National Institutes for Quantum and Radiological Science and Technology, Tokai, Ibaraki, Japan. He has studied radiation damage to DNA and its repair in living cells from the point of view of physicochemical processes.

Takehiko Ogawa is a Professor in the Department of Biopharmaceutical and Regenerative Sciences, Institute of Molecular Medicine and Life Science, Yokohama City University Association of Medical Science, Yokohama, Japan. He has studied germ cells as his life work, especially the development of in vitro spermatogenesis.

Kevin M. Prise is the Deputy Director and Professor of Radiation Biology at the Centre for Cancer Research and Cell Biology, Queen?s University Belfast, Belfast, UK. His recent work involved developing new biological based models for optimising advanced radiotherapies.

Additional information

Funding

This work was supported by Nakayama Foundation for Human Science, Yokohama City University Gushinkai Alumni Association, Marubun Research Promotion Foundation.