Contrastingly, an earlier study in a rat model of retinopathy in diabetes reported that increased TLR4 in retinal extracts was associated with disease progression [19] and that the blockade of the TLR4 signaling pathway reduced inflammation [19,20,21], thus indicating that the TLR4 signaling must be tightly regulated to prevent excessive inflammation. This evidence concerns the gene TLR4 and retinal disorder.