Hydrogen sulfide protects retina from blue light-induced photodamage and degeneration via inhibiting ROS-mediated ER stress-CHOP apoptosis signal.

Hydrogen sulfide (HS) is a small reducing gas molecule with various biological functions such as anti-oxidative, anti-apoptotic and anti-inflammatory activities. In this study, we investigated the therapeutic effects of exogenous HS in the experimental models of retinal photodamage in vivo and in vitro. Rats with open eyelids were pretreated with HS (80120 μmol/kg) for 10 days and then continuously exposed to blue light (435445nm, 11.2W/m2) for 8 h to establish in vivo experimental model. ARPE-19 cells were pretreated with HS and then exposed to blue light to establish in vitro experimental model. In vivo experiments, HS significantly ameliorated blue light-induced retinal oxidative stress, apoptosis and degeneration. Moreover, HS inhibited the activation of blue light-induced endoplasmic reticulum (ER) stress CHOP apoptotic signaling. In vitro experiments, HS improved blue light-induced oxidative stress and oxidative damage. HS inhibited ROS-mediated activation of ER stress CHOP apoptotic signaling. HS alleviated blue light-induced apoptosis and increases cell viability. The ER stress inhibitor 4-PBA alleviated blue light-induced apoptosis and increases cell viability. Taken together, these results indicate that HS can inhibit ROS-mediated ER stress-CHOP apoptosis signal, thereby alleviating blue light-triggered retinal apoptosis and degeneration.