Abstract:AIM: To investigate the protective effect and mechanism of quercetin on age-related macular degeneration in mice through Nrf2/Keap1/ARE pathway.
METHODS: Kunming mice were used as research objects, which were divided into control group, model group and quercetin group. Fundus examination was showed whether yellow-white like glassy sputum substances appeared in the fundus of each group of mice; OCT was used to examine the retinal thickness of each group of mice; HE staining was used to observe the changes of retinal morphology in each group of mice; FFA was observed the fundus vascular integrity of each group of mice. The activities of SOD, GSH-Px, CAT and the contents of ROS and MDA in serum were detected by ELISA; Western blot was used to detect the expression of Nrf2/Keap1/ARE related proteins in the retina of each group.
RESULTS: Quercetin can reduce the yellow and white glassy wart substance in the fundus of mice and increase the thickness of the retina(P<0.05), and the points of retinal vascular leakage is significantly reduced. Compared with the model group, the a-wave amplitude and b-wave amplitude of the quercetin group were significantly higher than those of the model group(P<0.01); Quercetin can make the retinal structure of mice clearer, necrosis and shed part of the outer nuclear layer, and reduce the content of ROS and MDA in mouse serum(all P<0.05), and increase the activities of SOD, GSH-Px, and CAT(all P<0.05). Compared with the model group, the expression of Nrf2 protein in the retinal cytoplasm of mice in the quercetin group was up-regulated(P<0.05), and the expression of Nrf2 protein in the nucleus was down-regulated(P<0.05), GCL protein expression was down-regulated(P<0.05).
CONCLUSION: Quercetin improved the oxidative stress state after retinal photodamage through the Nrf2/Keap1/ARE pathway, protected the retinal function, and protected against age-related macular degeneration.