Diabetic retinopathy (DR) is a leading cause of vision impairment in the working-age population worldwide. Various modes of photoreceptor cell death contribute to the development of DR, including apoptosis and autophagy. However, whether ferroptosis is involved in the pathogenesis of photoreceptor degeneration in DR is still unclear. High-glucose (HG)-stimulated 661W cells and diabetic mice models were used for in vitro and in vivo experiments, respectively. The levels of intracellular iron, glutathione (GSH), reactive oxygen species (ROS), lipid peroxidation (MDA), and ferroptosis-related proteins (GPX4, SLC7A11, ACSL4, FTH1, and NCOA4) were quantified to indicate ferroptosis. The effect of ferroptosis inhibition was also assessed. Our data showed the levels of iron, ROS, and MDA were enhanced and GSH concentration was reduced in HG-induced 661W cells and diabetic retinas. The expression of GPX4 and SLC7A11 was downregulated, while the expression of ACSL4, FTH1, and NCOA4 was upregulated in the 661W cells cultured under HG conditions and in the photoreceptor cells in diabetic mice. Furthermore, the administration of the ferroptosis inhibitor ferrostatin-1 (Fer-1) obviously alleviated ferroptosis-related changes in HG-cultured 661W cells and in retinal photoreceptor cells in diabetic mice. Taken together, our findings suggest that ferroptosis is involved in photoreceptor degeneration in the development of the early stages of DR.
To report a case series in which a modified technique was used to remove retained submacular perfluorocarbon liquid (PFCL) secondary to vitreoretinal surgery for rhegmatogenous retinal detachment. Four patients who had undergone pars plana vitrectomy for rhegmatogenous retinal detachment were further treated with surgical intervention because of retained submacular PFCL. With a three-port pars plana approach, after the internal limiting membrane peeling with indocyanine green staining, a 38-gauge flexible cannula was used to aspirate the submacular perfluorocarbon bubble, followed by fluid-air exchange and air injection into vitreous cavity. Submacular perfluorocarbon liquid was removed successfully and visual acuity had an improvement in all cases. The surgical removal of retained submacular PFCL using a 38-gauge flexible cannula combined with internal limiting membrane peeling and intravitreal air tamponade may provide anatomical and visual satisfactory outcomes.