Sleep deprivation disrupts the lacrimal system and induces dry eye disease

Sleep deficiency is a common public health problem associated with many diseases, such as obesity and cardiovascular disease. In this study, we established a sleep deprivation (SD) mouse model using a ‘stick over water’ method and observed the effect of sleep deficiency on ocular surface health. We found that SD decreased aqueous tear secretion; increased corneal epithelial cell defects, corneal sensitivity, and apoptosis; and induced squamous metaplasia of the corneal epithelium. These pathological changes mimic the typical features of dry eye. However, there was no obvious corneal inflammation and conjunctival goblet cell change after SD for 10 days. Meanwhile, lacrimal gland hypertrophy along with abnormal lipid metabolites, secretory proteins and free amino-acid profiles became apparent as the SD duration increased. Furthermore, the ocular surface changes induced by SD for 10 days were largely reversed after 14 days of rest. We conclude that SD compromises lacrimal system function and induces dry eye. These findings will benefit the clinical diagnosis and treatment of sleep-disorder-related ocular surface diseases. New insights into the effects of sleep deprivation on the eyes will inform treatment of sleep disorders. Eye surface tissues suffer severe damage if stable tear production stops and the eyes dry out. Wei Li and Zuguo Liu at Xiamen University in Fujian, China, and co-workers investigated the effect of sleep deprivation on eye health in mice. Within two days, sleep-deprived mice secreted fewer tears, showed defects in corneal cells and corneal sensitivity, and had enlarged lacrimal glands. These symptoms mimic those of dry eye disease, but sleep-deprivation dry eye has unique characteristics that should be considered during treatment. The study pointed out that lacrimal system is very sensitive to sleep deprivation, more attention should be paid to sleep deficiency induced eye problems, such as dry eye.