Blue light pollution induces dry eye by damaging conjunctival stem cells through cAMP-PKA-Pax6 signaling pathway.

Purpose: Blue light exposure constitutes a risk factor for dry eye. The research explores the influence of conjunctival stem cells (CjSCs) by blue light, elucidating the pathogenesis of blue light-induced dry eye.

Materials And Methods: Primary SD rat CjSCs and rats were irradiated with blue light at 460 nm. The impact of blue light illumination on both CjSCs and rats was examined, and RNA-sequencing (RNA-seq) identified the specific mechanisms. Additionally, blue light-irradiated rats and primary CjSCs were treated with Forskolin to validate the effects of the cAMP-PKA pathway on CjSCs differentiation and blue light-induced dry eye.

Results: Blue light exposure not only affected the stemness and proliferation of CjSCs, but also disturbed the differentiation by down-regulating the expression of Pax6. Mechanically, the cAMP-PKA signaling pathway was significantly inhibited following blue light emission. Reduced P-PKA expression affected Pax6 transcription, which in turn promoted abnormal differentiation of CjSCs. Moreover, Forskolin, a specific agonist of cAMP-PKA, effectively rescued the drawback of blue light irradiation on CjSCs.

Conclusions: Blue light exposure results in abnormal differentiation in CjSCs through the down-regulation of the expression of Pax6 via the cAMP-PKA signaling pathway. The abnormal differentiation in CjSCs should be pursued as a novel target for protection against blue light-induced dry eye.