Ultrastructural Analysis of Large Japanese Field Mouse (<i>Apodemus speciosus</i>) Testes Exposed to Low-Dose-Rate (LDR) Radiation after the Fukushima Nuclear Power Plant Accident
Marta Gatti,
Manuel Belli,
Mariacarla De Rubeis,
Syun Tokita,
Hikari Ikema,
Hideaki Yamashiro,
Yohei Fujishima,
Donovan Anderson,
Valerie Swee Ting Goh,
Hisashi Shinoda,
Akifumi Nakata,
Manabu Fukumoto,
Tomisato Miura,
Stefania Annarita Nottola,
Guido Macchiarelli,
Maria Grazia Palmerini
Affiliations
Marta Gatti
Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00161 Rome, Italy
Manuel Belli
Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, 00166 Rome, Italy
Mariacarla De Rubeis
Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00161 Rome, Italy
Syun Tokita
Graduate School of Science and Technology, Niigata University, Niigata 959-2181, Japan
Hikari Ikema
Graduate School of Science and Technology, Niigata University, Niigata 959-2181, Japan
Hideaki Yamashiro
Graduate School of Science and Technology, Niigata University, Niigata 959-2181, Japan
Yohei Fujishima
Department of Risk Analysis and Biodosimetry, Institute of Radiation Emergency Medicine, Hirosaki University, Aomori 036-8564, Japan
Donovan Anderson
Department of Risk Analysis and Biodosimetry, Institute of Radiation Emergency Medicine, Hirosaki University, Aomori 036-8564, Japan
Valerie Swee Ting Goh
Department of Radiobiology, Singapore Nuclear Research and Safety Initiative, National University of Singapore, Singapore 138602, Singapore
Hisashi Shinoda
Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan
Akifumi Nakata
Department of Life Science, Faculty of Pharmaceutical Sciences, Hokkaido University of Science, Hokkaido 006-8585, Japan
Manabu Fukumoto
RIKEN Center for Advanced Intelligence Project, Pathology Informatics Team, Tokyo 103-0027, Japan
Tomisato Miura
Department of Risk Analysis and Biodosimetry, Institute of Radiation Emergency Medicine, Hirosaki University, Aomori 036-8564, Japan
Stefania Annarita Nottola
Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00161 Rome, Italy
Guido Macchiarelli
Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy
Maria Grazia Palmerini
Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy
Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, great attention has been paid to the impact of chronic low-dose-rate (LDR) radiation exposure on biological systems. The reproductive system is sensitive to radiation, with implications connected to infertility. We investigated the testis ultrastructure of the wild large Japanese field mouse (Apodemus speciosus) from three areas contaminated after the FDNPP accident, with different levels of LDR radiation (0.29 µSv/h, 5.11 µSv/h, and 11.80 µSv/h). Results showed good preservation of the seminiferous tubules, comparable to the unexposed animals (controls), except for some ultrastructural modifications. Increases in the numerical density of lipid droplet clusters in spermatogenic cells were found at high levels of LDR radiation, indicating an antioxidant activity rising due to radiation recovery. In all groups, wide intercellular spaces were found between spermatogenic cells, and cytoplasmic vacuolization increased at intermediate and high levels and vacuolated mitochondria at the high-level. However, these findings were also related to the physiological dynamics of spermatogenesis. In conclusion, the testes of A. speciosus exposed to LDR radiation associated with the FDNPP accident showed a normal spermatogenesis, with some ultrastructural changes. These outcomes may add information on the reproductive potential of mammals chronically exposed to LDR radiation.
