title: Hydrogen-rich saline attenuates radiation-induced male germ cell loss in mice through reducing hydroxyl radicals.
abstract: Our recent studies suggest that H2 (hydrogen) has a potential as a novel radioprotector without known toxic side effects. The present study was designed to examine the underlying radioprotective mechanism of H2 and its protective role on irradiated germ cells. Produced by the Fenton reaction and radiolysis of H2O, hydroxyl radicals (•OH) were identified as the free radical species that were reduced by H2. We used a H2 microelectrode to dynamically detect H2 concentration in vivo, and found H2 significantly reduced in situ fluorescence intensity of hydroxyphenyl fluorescein; however, as we treated the mice with H2 after irradiation, the decrease is not significant. We found that pre-treatment of H2 to IR (ionizing radiation) significantly suppressed the reaction of •OH and the cellular macromolecules which caused lipid peroxidation, protein carbonyl and oxidatively damaged DNA. The radioprotective effect of H2 on male germ cells was supported by ameliorated apoptotic findings examined by morphological changes and TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling) in testicular tissue, and by preserved viability of stem spermatogonia examined for testicular histological parameters, daily sperm production and sperm quality; we used WR-2721 [S-2-(3-aminopropylamino)ethyl phosphorothioic acid] as a reference compound. Our results represent the first in vivo evidence in support of a radioprotective role of H2 by neutralizing •OH in irradiated tissue with no side effects.
authors.affiliation: Department of Radiation Medicine, Faculty of Naval Medicine, Second Military Medical University, Shanghai, People's Republic of China.
authors.forename: Yunhai
authors.initials: Y
authors.lastname: Chuai
authors.forename: Fu
authors.initials: F
authors.lastname: Gao
authors.forename: Bailong
authors.initials: B
authors.lastname: Li
authors.forename: Luqian
authors.initials: L
authors.lastname: Zhao
authors.forename: Liren
authors.initials: L
authors.lastname: Qian
authors.forename: Fei
authors.initials: F
authors.lastname: Cao
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Xuejun
authors.initials: X
authors.lastname: Sun
authors.forename: Jianguo
authors.initials: J
authors.lastname: Cui
authors.forename: Jianming
authors.initials: J
authors.lastname: Cai
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016166:Free Radical Scavengers / Q000494:pharmacology; D005720:Gamma Rays; D005854:Germ Cells / Q000187:drug effects / Q000528:radiation effects*; D006859:Hydrogen / Q000494:pharmacology*; D017665:Hydroxyl Radical / Q000494:pharmacology; D008297:Male; D051379:Mice; D018384:Oxidative Stress / Q000187:drug effects; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D012965:Sodium Chloride / Q000494:pharmacology; D013737:Testis / Q000166:cytology
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D011837:Radiation-Protective Agents; D017665:Hydroxyl Radical; D012965:Sodium Chloride; D006859:Hydrogen