Effects Of Ginkgo Biloba Polysaccharide Degradation Products On Anti-Inflammatory And Antioxidant Activities Of Macrophages

China is rich in Ginkgo biloba resources,and Ginkgo biloba production accounts for more than 70%of the world.It is known that Ginkgo biloba polysaccharide extracted from Ginkgo biloba have anti-tumor,antioxidant,anti-inflammatory and other biological activities.However,because of its large molecular weight,it is difficult to break through the cell barrier,which restricts its activity and causes a great waste of resources.This test will degrade the polysaccharides of Ginkgo biloba,and systematically explain the changes in the activity of polysaccharide after degradation by examining their effects on free radicals,lipid peroxides and inflammatory mediators.The test content is as follows:In this study,the chemical method was first used to degrade the polysaccharide of Ginkgo biloba and GPC method was used to determine the molecular weight.Then the MTT method was used to determine the safe concentration of degraded Ginkgo biloba polysaccharide and LPS on RAW264.7 macrophages.The relative expression of IL-1βand IL-6 mRNA was used to establish a cell model.When verifying the determination of the antioxidant properties of the degraded polysaccharide of Ginkgo biloba,the ability of Ginkgo biloba polysaccharide to remove DPPH and O^2-·before and after degradation at different concentrations was tested;then the blank group（CON）,model group（LPS）,and undegraded ginkgo leaves were set The polysaccharide group（LPS+GBLP）and the low-medium-high-degradation Ginkgo biloba polysaccharide group（LPS+DGBLP）totaled six groups.The effects of degradation of Ginkgo biloba polysaccharide on MDA and SOD of RAW264.7 macrophages were determined by biochemical methods.For the effects of degradation of Ginkgo biloba polysaccharide on the anti-inflammatory activity of RAW264.7cells,three groups of blank group（CON）,model group（LPS）,undegraded ginkgo biloba polysaccharide group（LPS+GBLP）,and low,medium and high degradable ginkgo biloba polysaccharide（LPS+DGBLP）were divided into six groups,and the secretion and expression of intracellular inflammatory mediators were detected by ELISA and fluorescent quantitative PCR.The test results showed that the molecular weight of Ginkgo biloba leaf polysaccharide after degradation was reduced from 194190 Da to 26410 Da;when the concentration of degraded Ginkgo biloba leaf polysaccharide was 16μg/mL,32μg/mL,64μg/mL,RAW264.7 cell viability was not significantly different from the blank group;The optimal concentration of LPS in the cell model is 1μg/mL;after detecting the degradation of Ginkgo biloba leaf polysaccharides to DPPH and O^2-·clearance,it is found that the degraded Ginkgo biloba leaf polysaccharides have good antioxidant activity in vitro;In the study of the effects of RAW264.7 macrophage oxidative stress,it was found that compared with the model group,the addition of degraded Ginkgo biloba polysaccharide can inhibit the content of intracellular MDA and promote the production of SOD;in terms of anti-inflammatory,the degradation of Ginkgo biloba polysaccharide can be different Inhibits the secretion and expression of TNF-α,IL-1β,IL-6,IL-8,COX-2,iNOS,IL-10,and promotes the production of TGF-β1.In summary,the molecular weight of Ginkgo biloba polysaccharide is reduced,which can effectively scavenge free radicals and inhibit LPS-induced RAW264.7 macrophages from oxidative stress and inflammatory responses.It is superior to Ginkgo biloba polysaccharide at high doses.