Study On The Mechanism Of AMD In Young Mice Induced By High GI Diet

Objective The aim of this study was to establish a model of age-related macular degeneration(AMD)in young mice induced by Glycemic Index(GI)Diet,and to investigate the role of persistent hyperglycemia in the development of AMD,the aim of this study was to observe the effect of early dietary adjustment on the development of AMD.Methods Sixty C57 BL / 6J wild type male mice were randomly divided into three groups: low GI diet Group(LG Group),high GI diet Group(Hg Group)and high GI diet switch to low GI diet Group(HGxo LG Group).The LG group was fed with 70%amylose + 30% amylopectin for 12 months,the HG group with 100% amylopectin for12 months,and the HGxo LG group with 100% amylopectin for 6 months were fed with 70% amylopectin + 30% amylopectin for 6 months.The weight of the mice was measured weekly,Fasting Blood Glucose was measured monthly and glucose tolerance was tested,and fundus photographs were taken every two months.All data were analyzed with SPSS 16.0 software.Results There was no difference in the body weight of the three groups before entering the group(p > 0.05).The weight gain of HG group was faster than that of LG Group.The 15-month-old HGxo LG mice were about 10% heavier than the LG mice.The Fasting Blood Glucose and glucose tolerance test were normal in the LG group and the low GI Diet HGxo LG group,while the Hg Group and on the High GI Diet HGxo LG Group had high fasting blood glucose but did not meet the standard of diabetes,the glucose tolerance of Hg group mice was impaired.The Retina of the LG group was healthy,the retina was reddish,the blood vessels were radially distributed around the optic disc and the optic papilla was ruddy.In HG group,there were obvious spots in the retina at 11 months of age,which might correspond to the local pigmentation area,there is a dome-shaped edge sharp,whitish color of small and hard glass film wart-like Deposits.Between the ages of 12 and 15 months,there is an increased amount of vitreous verrucous deposits on the retina,which are larger,yellowing in color,blurred borders,and atrophy of the RPE around the central part of the retina and bright,highly reflective areas,these phenomena are similar to the retinal manifestations of dry AMD in humans.In HGxo LG group,the Retina of9-month-old mice after 6 months on a high-GI Diet showed scattered spots,which disappeared when HGxo LG mice switched to a low-GI Diet.Conclusion Wild-type C57 BL / 6J mice were fed with high GI diet to establish a human dry AMD model,which showed retinal injury and RPE abnormality very similar to that of human dry AMD.The effects and progression of AMD were delayed by a low GI Diet compared with a high GI diet.A High GI Diet was associated with an increased risk of retinal damage compared to a low GI Diet.Retinal damage from a high GI diet can be arrested or reversed after a diet change to a low GI Diet.