Hydrogen alleviates high-level low-dose irradiation-induced injury of male reproductive system in mice / 第二军医大学学报

ABSTRACT

Objective To explore the protective effects of molecular hydrogen on high-level low-dose irradiation-induced male reproductive system injury in mice and the underlying mechanism. Methods Cultured spermatogonia-derived cell line GC-1 spg was randomized into control group, hydrogen group, 4 Gy radiation group and 4 Gy radiation+hydrogen group. The apoptotic rate of the cells was detected by flow cytometry assay at 24 h after treatment in each group. Seventy-two male BALB/c mice were randomized into control group, hydrogen group, 0.25 Gy radiation group, 0.25 Gy radiation+ hydrogen group, 0.5 Gy radiation group and 0.5 Gy radiation+hydrogen group, with 12 mice in each group. The hydrogen treatment was conducted by hydrogen-rich water administration and high-concentration hydrogen gas inhalation. At 24 h after treatment, the testes were dissected and sectioned for H-E staining, and blood samples from the internal canthus vein were collected to determine the levels of gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone using ELISA. At 4 weeks after radiation, the bilateral epididymides were isolated to prepare sperm suspensions, and the DNA damage of the spermatozoa was examined using the neutral single cell gel electrophoresis. Results The 24 h apoptosis rate of GC-1 spg cells was significantly decreased in the 4 Gy radiation+hydrogen group compared with the 4 Gy radiation group (t=7.186, P<0.01). Hydrogen obviously reverted the histological damage of the testes induced by 0.5 Gy irradiation, significantly inhibited 0.25 Gy and 0.5 Gy radiation-caused surge of FSH (t=3.195 8, P=0.019; t=10.723 4, P<0.05), and significantly ameliorated comet tailing and damage of the sperm DNA at 4 weeks after radiation (tail area t0.25 Gy=16.592 3, t0.5 Gy=15.891 5; tail DNA t0.25 Gy=11.296 5, t0.5 Gy=13.785 0; tail DNA% t0.25 Gy=26.834 0, t0.5 Gy=10.325 7; tail length t0.25 Gy=16.865 4, t0.5 Gy=15.441 2; tail moment t0.25 Gy=26.979 4, t0.5 Gy=13.174 2; Olive tail moment t0.25 Gy=24.752 4,t0.5 Gy=6.896 1; all P<0.05). Conclusion Molecular hydrogen protects male mouse reproductive system from high-level low-dose radiation through reducing spermatogonium apoptosis, adjusting hormone disturbance and ameliorating sperm DNA damage.