MA Lingyi, LI Weixi, YIN Jiechen, ZHU Guangcan, LIU Ran. Reproductive toxicity of environmentally relevant concentrations of testosterone on Caenorhabditis elegans[J]. Journal of Environmental and Occupational Medicine, 2021, 38(8): 910-914. DOI: 10.13213/j.cnki.jeom.2021.20581
Citation: MA Lingyi, LI Weixi, YIN Jiechen, ZHU Guangcan, LIU Ran. Reproductive toxicity of environmentally relevant concentrations of testosterone on Caenorhabditis elegans[J]. Journal of Environmental and Occupational Medicine, 2021, 38(8): 910-914. DOI: 10.13213/j.cnki.jeom.2021.20581

Reproductive toxicity of environmentally relevant concentrations of testosterone on Caenorhabditis elegans

  • Background Testosterone is an important androgen. However, human production and living activities have led to its exposure to varying degrees in the environment, which may affect the reproductive ability of many organisms in the ecological environment.
    Objective Caenorhabditis elegans (C. elegans) is used as a model organism to investigate the reproductive toxicity of testosterone at environmentally relevant concentrations.
    Methods According to the actual concentration of testosterone in the environment, synchronized L1-stage wild-type N2 nematodes were exposed to representative environmentally relevant concentrations (1 ng·L-1, 10 ng·L-1, 100 ng·L-1, 1 μg·L-1, 10 μg·L-1) of testosterone and M9 solvent (control) at 20℃ for 48 h. Brood size, generation time, gonadal development stage, malformation, and the number of germ cells were observed among the groups.
    Results After the wild-type N2 C. elegans being exposed to testosterone for 48 h in the L1 stage, compared with the control group (219.70±27.99), the brood sizes of C. elegans were significantly decreased in the 10 ng·L-1 to 10 μg·L-1 groups (186.90±19.68, P=0.009; 182.60±25.33, P=0.003; 178.20±14.46, P=0.001; 159.20±28.64, P < 0.001, respectively) (F=7.24, P < 0.001), and in the 10 μg·L-1 group the brood size decreased by 27.5%. Compared with the control group(71.85±3.49) h, the generation time was significantly prolonged in the 100 ng·L-1 group(81.70±6.26) h, P=0.001, 1 μg·L-1 group(79.28±4.83) h, P=0.015, and 10 μg·L-1 group(79.54±3.92) h, P=0.011 (F=3.97, P=0.005), and was longest in the 100 ng·L-1 group where the generation time was prolonged by 9.85 h. In terms of gonadal development stage, as the concentration of testosterone increased, the development of gonads was gradually inhibited, and the proportion of adult worms to total nematodes gradually decreased from (63.82±16.37)% in the control group to (53.95±1.03)%, (41.39±8.57)%, (26.79±1.31)%, (20.16±1.94)%, and (8.00±2.03)% in each dose group, respectively. Malformations were observed in the 100 ng·L-1 group and above, including ovulation hole malformation, unfertilized eggs in uterus, a bag of worm, and abnormal gonadal development. Compared with the control group (249.40±23.09), the numbers of germ cells were significantly declined in the 10 ng·L-1 to 10 μg·L-1 groups (224.50±28.48, P=0.048; 215.20±27.28, P=0.005; 194.30±26.78, P < 0.001; 181.80±19.45, P < 0.001, respectively) (F=10.64, P < 0.001), and in the 10 μg·L-1 group the number of germ cells decreased by 27.1%.
    Conclusion Androgen testosterone at environmentally relevant concentrations can lead to decreased brood size, prolonged generation time, and delayed gonadal development of C. elegans. These effects may be related to the decrease of germ cells.
  • loading

Catalog

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return