Ferroptosis mediates retinal damage caused by the combined effects of sleep deprivation and light damage.

BACKGROUND

Sleep deprivation (SD) and excessive light exposure (LD) are increasingly prevalent stressors in modern life, yet their combined impact on retinal integrity remains unclear. This study investigates how SD amplifies LD-induced retinal injury and explores the mechanistic role of ferroptosis-a regulated, iron-dependent form of lipid peroxidation-driven cell death.

METHODS

We established a dual-stressor mouse model with four groups: control, SD, LD, and SD + LD. Retinal structure and function were evaluated via OCT, ERG, histology, and behavioral tests. Mechanistic insights were obtained from transcriptomic profiling, immunostaining, electron microscopy, and pharmacological inhibition using Liproxstatin-1 (Lip-1).

RESULTS

While SD alone caused no overt damage, SD + LD synergistically exacerbated retinal degeneration. Transcriptomic and molecular analyses revealed pronounced ferroptosis activation in the SD + LD group-marked by reduced antioxidant defenses (↓GPX4, xCT, GCH1, FSP1), elevated lipid peroxidation (↑4-HNE, MDA, ALOX15, ACSL4), disrupted iron homeostasis (↑HO-1, ↓FPN, ↓FTH1), and mitochondrial shrinkage. Lip-1 treatment reversed these changes and preserved retinal function.

CONCLUSION

Short-term sleep deprivation exacerbated light-induced retinal injury by promoting ferroptosis, as indicated by disrupted antioxidant capacity, enhanced lipid peroxidation, and disturbed iron homeostasis. Treatment with Lip-1 substantially attenuated these changes.