Ankara Bilkent City Hospital, Clinic of Pediatric Endocrinology, Ankara, Turkey
Gazi University Faculty of Medicine, Department of Pediatric Endocrinology, Ankara, Turkey
J Clin Res Pediatr Endocrinol. 2023 Nov 22;15(4):365-374. doi: 10.4274/jcrpe.galenos.2023.2022-12-1. Epub 2023 May 22.
This study was designed to examine the effect of blue light exposure and exposure time on puberty in an animal model.
Eighteen 21-day-old female Sprague Dawley rats were divided into three equal groups which were: control group (CG); blue light-6 hours (BL-6); and blue light-12 hours (BL-12). CG rats were maintained with 12/12-hour light-dark cycles. The animals in BL-6 and BL-12 were exposed to blue light of wavelength 450-470 nm and intensity of 0.03 uW/cm for 6 and 12 hours, respectively. Exposure to blue light continued until the first signs of puberty. Serum follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol, testosterone, dehydroepiandrosterone sulfate (DHEA-S), leptin and melatonin were measured. Subsequently the ovaries and uterus were examined histomorphologically.
The median day of puberty start was 38, 32 and 30 for the CG, BL-6, and BL-12 groups, respectively (p=0.001). FSH, testosterone, DHEA-S, and leptin concentrations of all groups were similar. However, LH and estradiol concentrations in BL-6 were higher compared to CG (p=0.02). There was a negative correlation between blue light exposure, exposure time, and melatonin concentrations (r=-0.537, p=0.048). Ovarian tissue was compatible with puberty in all groups. As blue light exposure time increased, capillary dilatation and edema in the ovarian tissue increased. Prolonged exposure was associated with polycystic ovary-like (PCO) morphological changes and apoptosis in granulosa cells.
These results suggest that exposure to blue light and the duration of exposure induced earlier puberty in female rats. As the duration of blue light exposure increased, PCO-like inflammation, and apoptosis were detected in the ovaries.
本研究旨在通过动物模型研究蓝光照射和照射时间对青春期的影响。
将 18 只 21 天大的雌性 Sprague Dawley 大鼠分为三组：对照组（CG）、蓝光 6 小时组（BL-6）和蓝光 12 小时组（BL-12）。CG 大鼠保持 12/12 小时光照/黑暗循环。BL-6 和 BL-12 组的动物分别暴露于波长为 450-470nm、强度为 0.03uW/cm 的蓝光下 6 小时和 12 小时。暴露于蓝光持续到青春期开始的第一迹象。测量血清卵泡刺激素（FSH）、黄体生成素（LH）、雌二醇、睾酮、硫酸脱氢表雄酮（DHEA-S）、瘦素和褪黑素。随后检查卵巢和子宫的组织形态学。
CG、BL-6 和 BL-12 组的青春期开始中位数分别为 38、32 和 30 天（p=0.001）。所有组的 FSH、睾酮、DHEA-S 和瘦素浓度相似。然而，BL-6 中的 LH 和雌二醇浓度高于 CG（p=0.02）。蓝光暴露、暴露时间与褪黑素浓度之间存在负相关（r=-0.537，p=0.048）。所有组的卵巢组织均与青春期一致。随着蓝光暴露时间的增加，卵巢组织中的毛细血管扩张和水肿增加。长时间暴露与多囊卵巢样（PCO）形态改变和颗粒细胞凋亡有关。
这些结果表明，蓝光暴露和暴露时间会导致雌性大鼠青春期提前。随着蓝光暴露时间的延长，卵巢中会出现 PCO 样炎症和细胞凋亡。
