Background: Diminished ovarian reserve is increasingly reported in young women as well, it is an important cause of infertility. Widespread screen use and artificial lighting have increased exposure to blue light in the short-wavelength range, which may threaten ovarian reserve (OR). Growth hormone (GH) may counteract this injury by modulating the insulin‑like growth factor‑1/insulin‑like growth factor‑1 receptor (IGF‑1/IGF‑1R) axis. Aim: To evaluate the impact of blue light on OR and determine whether GH protects the ovary through IGF‑1/IGF‑1R restoration. Methods: After 7 days of acclimatization, twenty‑four prepubertal female rats were randomized into four groups (n = 6) for a 10‑day experiment: control (natural room light, saline subcutaneous (s.c.) once daily from day 4 to day 10); GH (natural room light, GH 1 mg/kg s.c. from day 4 to 10); blue light (450–480 nm for 12 h/night, 6:00 p.m.–6:00 a.m., from day 1 to day 10 plus saline s.c. from day 4 to 10); and blue light + GH (same light protocol plus GH 1 mg/kg s.c. from day 4 to 10). On day 11, estradiol, FSH, anti‑Müllerian hormone (AMH), melatonin, oxidative‑stress markers (GSH, MDA), caspase‑3, and serum and ovarian IGF‑1 were determined, and ovarian IGF‑1R immunohistochemistry with histopathology were performed. Results: Blue light significantly reduced estradiol, AMH, melatonin, serum and ovarian IGF‑1, and GSH, while increasing MDA, caspase‑3, and IGF‑1R expression. GH co‑treatment reversed these changes. Conclusion: Blue‑light exposure impairs OR through oxidative and apoptotic mechanisms and disruption of the IGF‑1/IGF‑1R axis, while GH exerts a potent photoprotective effect. |
