Ogo Fernanda Mithie, Siervo Glaucia Eloisa Munhoz Lion, de Moraes Ana Maria Praxedes, Machado Katia Gama de Barros, Scarton Suellen Ribeiro da Silva, Guimarães Ana Tereza Bittencourt, Cecchini Alessandra Lourenço, Simão Andréa Name Colado, Mathias Paulo Cezar de Freitas, Fernandes Glaura Scantamburlo Alves
Department of General Biology, Biological Sciences Center, State University of Londrina - UEL, Londrina, Paraná, Brazil.
Department of Pathological Sciences, Biological Sciences Center, State University of Londrina - UEL, Londrina, Paraná, Brazil.
J Dev Orig Health Dis. 2021 Aug;12(4):595-602. doi: 10.1017/S2040174420000975. Epub 2020 Oct 28.
Alterations in the circadian cycle are known to cause physiological disorders in the hypothalamic-pituitary-adrenal and the hypothalamic-pituitary-gonadal axes in adult individuals. Therefore, the present study aimed to evaluate whether exposure of pregnant rats to constant light can alter the reproductive system development of male offspring. The dams were divided into two groups: a light-dark group (LD), in which pregnant rats were exposed to an LD photoperiod (12 h/12 h) and a light-light (LL) group, in which pregnant rats were exposed to a photoperiod of constant light during the gestation period. After birth, offspring from both groups remained in the normal LD photoperiod (12 h/12 h) until adulthood. One male of each litter was selected and, at adulthood (postnatal day (PND) 90), the trunk blood was collected to measure plasma testosterone levels, testes and epididymis for sperm count, oxidative stress and histopathological analyses, and the spermatozoa from the vas deferens to perform the morphological and motility analyses. Results showed that a photoperiod of constant light caused a decrease in testosterone levels, epididymal weight and sperm count in the epididymis, seminiferous tubule diameter, Sertoli cell number, and normal spermatozoa number. Histopathological damage was also observed in the testes, and stereological alterations, in the LL group. In conclusion, exposure to constant light during the gestational period impairs the reproductive system of male offspring in adulthood.
已知昼夜节律周期的改变会导致成年个体下丘脑 - 垂体 - 肾上腺轴和下丘脑 - 垂体 - 性腺轴出现生理紊乱。因此，本研究旨在评估孕期大鼠持续光照是否会改变雄性后代的生殖系统发育。将孕鼠分为两组：明暗组（LD），孕鼠在此组中暴露于明暗光周期（12小时/12小时）；持续光照组（LL），孕鼠在此组中在妊娠期暴露于持续光照光周期。出生后，两组后代均保持在正常的明暗光周期（12小时/12小时）直至成年。每窝选取一只雄性，在成年期（出生后第90天）采集躯干血液以测量血浆睾酮水平，采集睾丸和附睾用于精子计数、氧化应激和组织病理学分析，并采集输精管中的精子进行形态学和活力分析。结果显示，持续光照光周期导致睾酮水平、附睾重量和附睾精子计数、曲细精管直径、支持细胞数量以及正常精子数量下降。在持续光照组中，睾丸也观察到组织病理学损伤和体视学改变。总之，妊娠期暴露于持续光照会损害成年雄性后代的生殖系统。
