The Effect Of Polysaccharide Mixture In Jieduyizhifang On Oxidative Stress Gene Of AD Transgenic Nematodes

Objective:By studying the behavior and molecular aspects of AD transgenic nematodes through the polysaccharide mixture freeze-dried powder extracted from Jieduyizhifang,the thesis explores the expression of genes related to paralysis,death,and oxidative stress response of nematodes caused by A?aggregation at different concentrations of polysaccharide mixtures.And then to make sure whether the polysaccharide mixture can inhibit the paralysis of nematodes and if they can extend the life of nematodes,and whether they can reduce the occurrence of oxidative stress.Methods:The nematode CL4176 induced by A?_1-42 was used as the experimental model.There are four random groups,namely the control group and the administration group with the concentration of 20?g/mL,40?g/mL,80?g/mL.When doing the experiment related to the paralysis and life span,each group of 30 nematodes was cultured at 16?for48h and then transferred to 25?for 32h to observe the paralysis and death of nematodes,and record the data;during the oxidative stress gene expression experiment,300 nematodes per group are transferred to 25?for 48h,after incubation at 16?for 96 hours,and by extracting the RNA according to the instructions of the kit to determine the quantitative PCR in real time to detect the expression of genes related to oxidative stress.Repeat 3times for each experiment.Results:1.Paralysis behavior experiment:Behavioral experiments have initially confirmed that the three concentrations of the administration group can effectively inhibit AD nematode paralysis compared with the control group?P<0.05?,and the 80?g/mL administration group has the most significant inhibition effect?P<0.01?.2.Life test:Compared with the control group,the three concentrations of the administration groups can effectively prolong the survival rate of AD nematodes?P<0.05?.Among them,the 80?g/mL administration group has an average life extension of 23.97%compared with the control group?P<0.0 1?;the average life expectancy of 40?g/mL administration group was extended by 19.28%?P<0.05?,compared with the control group.3.Oxidative stress gene expression experiment:Compared with the control group,the expression level of daf-2 gene in the three concentration administration groups can be significantly reduced?P<0.01?;the 20?g/mL administration group's daf-16 and sod-3 gene expression levels were significantly up-regulated?P<0.05?;daf-16,sod-3 gene expression in nematodes in the 40?g/mL administration group was significantly up-regulated?P<0.01?,and gst-4 gene expression was significantly up-regulated?P<0.05?;In the 80?g/mL administration group,the gene expression of daf-16,sod-3,gst-4 gene was significantly increased?P<0.01?,and the expression of hsf-1 and hsp-16.2 genes was significantly increased?P<0.05?.Conclusion:1.The polysaccharide mixture in Jieduyizhifang can slow the paralysis of nematodes,extend the life of nematodes,and provide a reliable basis for neuroprotection.2.The protective effect of polysaccharide mixture on nematodes is achieved by regulating genes related to oxidative stress,which can up-regulate the expression levels of daf-16,hsf-1,hsp-16.2,sod-3,gst-4 genes and down-regulate daf-2.The amount of gene expression has a positive correlation with the concentration.3.For AD transgenic nematodes,in accordance with the principle o f early,sufficient and long-term medication,it can better exert neuroprotection and delay aging.