Naringin attenuates diabetic retinopathy by inhibiting inflammation, oxidative stress and NF-κB activation in vivo and in vitro.

OBJECTIVES: Naringin, an essential flavonoid, inhibits inflammatory response and oxidative stress in diabetes. However, whether naringin has beneficial effects on diabetic retinopathy (DR) remains unknown. MATERIALS AND METHODS: . RESULTS: Naringin alleviated DR symptoms as evidenced by the increased retinal ganglion cells and decreased GFAP level in rat retina. Naringin exhibited anti-inflammatory and antioxidative effects as confirmed by the down-regulated pro-inflammatory cytokines, tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), and the up-regulated antioxidants, glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) in DR rats. Moreover, we found that naringin inhibited HG-induced proliferation, abnormal inflammatory response and oxidative stress in rMC1 cells. In addition, the enhanced nuclear translocation of NF-κB p65 in diabetic rat retina and HG-induced rMC1 cells was suppressed by naringin. CONCLUSION: Naringin attenuates inflammatory response, oxidative stress and NF-κB activation in experimental models of DR.