A Study Of The Underlying Mechanism For ZJWJJF On Retina Of The Model Mice With Dry AMD Based On The Regulation Effect Of P62-keap1/Nrf2 Pathway

Objective:With C57BL/6 mice as the research object,the regulation of autophagy by the p62-keapl/Nrf2 pathway and the mechanism of retinal protection by Long Vistas Pill Variant Formula on oxidized-damaged mice were investigated in dry AMD model animals induced by a high-fat diet combined with hydroquinone intake.Methods:90 male C57BL/6 mice were randomly divided into 6 groups:the youth group,the elderly group,the model group,the treatment group(high,medium and low doses were set in the equivalent dose ratio table according to the surface area of human and animal bodies),among which the youth group and the elderly group received normal drinking water and diet.The model group and the dosing group were fed with high-fat diet and drinking water with hydroquinone added to the diet until the final concentration of 0.8%for 3 months to make dry AMD models.In the treatment group,low dose(165mg/kg/d),medium dose(330mg/kg/d),and high dose(660mg/kg/d)were treated by intragastric gavage for 3 months with Long Vistas Pill Variant Formula.Using fundus photography and autofluorescence observation glass membrane warts lesions,OCT scanning the entire retinal thickness change and the outer organization structure change,the morphology of tem observation of RPE cells,and the autophagosome evolution,sediment area under the RPE Bruch membrane thickness to evaluate the modeling situation and the protective effect of modified long vistas pill on the retina of oxidized mice.The ROS content of retina was detected by DCFH-DA method.The activity of retinal MDA was detected by colorimetric method.Transcription and protein expression of Nrf2,NQO-1,HO-1,p62,LC3?in retina were detected by western blot.Results:The retinal of model mice presented vitreous membrane vitreous lesions,the structure of the outer retinal tissue was disordered,the thickness of the retina became thinner,the IS/OS layer and the RPE cell layer were changed,the Bruch membrane was thickened under the electron microscope,the sediment accumulation under the RPE and other pathological manifestations,and the formation of autophagosomes and the ultrastructure of the membrane plate digestion process were observed.And the content of ROS MDA in retinal tissues increased.The treatment group mitigate retinopathy,and the contents of ROS and MDA were reduced.The high-dose group had the best effect,and the low-dose effect was not obvious,showing a dose-dependent relationship.Western blot results showed that the expression of Nrf2 protein in the cytoplasm of the model group was down-regulated,and the expression of Nrf2 protein in the nucleus was up-regulated.After drug intervention,the expression of Nrf2 in the cytoplasm of the model group was further decreased,and the expression of Nrf2 in the cytoplasm of the model group was significantly increased,and the effect was most pronounced in the high-dose group;The protein levels of HO-1 and NQO-1 in the model group were higher than those in the elderly group.However,the expression level of LC3? in the low-dose group was lower than that in the model group,while the expression level of LC3? in the middle-high dose group was higher than that in the model group.Conclusions:?High-fat diet and hydroquinone feeding can successfully simulate the animal model of dry AMD;?The mechanism of the effect of Long Vistas Pill Variant Formula could significantly reduce the retinal oxidative damage of model mice.When the body is damaged by oxidation,the content of ROS and MDA in the body increases,aggravating the degree of oxidative damage to the retina.On the one hand,Long Vistas Pill Variant Formula can reduce the damage to the retina of mice by reducing the content of reactive oxygen species and free radicals,and on the other hand,it can play an antioxidant role by initiating the Nrf2 pathway.The mechanism of action was as follows:Long Vistas Pill Variant Formula promoted the nuclear translocation of Nrf2,up-regulated the expression of HO-1 and NQO-1,and enhanced the scavenging of reactive oxygen species.At the same time,it can promote the upregulation of P62 protein,activate autophagy,promote the expression of LC3? protein,strengthen the self-protection effect,promote the repair of oxidative damage cells and reduce the oxidative damage of mouse retina,jointly maintain the oxidative balance of the body and provide double protection for RPE cells.In conclusion,Long Vistas Pill Variant Formula activated the antioxidant system and autophagy system through the p62-keapl/Nrf2 pathway,and jointly maintained the homeostasis of the internal environment,thus playing a protective role on the retina of mice with oxidative damage.