In our study, FKN was down‐regulated with diabetes progression accompanied by neuronal apoptosis in retinas of STZ‐induced diabetic rats and the in vitro study with glyoxal‐treated R28 cells indicated that the decreased FKN expression was at least partially due to the loss of retinal neurons in experimental DR (Figures 1, 2). Here, CX3CL1 is linked to diabetes mellitus.