Effects Of Tea Polyphenols EGCG On Gut Microbiota And Metabolism In Mice Based On Bioinformatics

In recent years,with the rapid development of bio-omics and high-throughput sequencing technologies,using bioinformatics analysis software and analysis methods to analyze biological big data,which can effectively and comprehensively reveal the biological mystery contained in huge and complex biological data.Epigallocatechin-3-gallate(EGCG)is a major polyphenol in tea,along with strong antioxidant activity,which can effectively scavenge free radicals and delay aging.However,its anti-aging mechanism is complicated and has not been fully elucidated yet.In this work,the aging model was established by continuous intraperitoneal injection of D-galactose.Using UPLC-QTOF/MS metabolomics analysis technology and Illumina MiSeq high-throughput sequencing technology,combined with bioinformatics methods,to study the effects of EGCG on gut microbiota and body metabolism in aging mice.and Moreover,the biological mystery of aging and mechanisms referring to the anti-aging activities of EGCG were revealed in the present study.Subsequently,the main research contents are summarized as follows:(1)D-galactose-induced aging mice model was established and used to investigate the activities of EGCG.In this work,mice were injected intraperitoneally with D-galactose for 10 weeks to establish the aging model.Data showed that the index of spleen,thymus and brain,learning-memory ability and the antioxidant capacities of liver and brain tissues of aging mice were reduced dramatically when compared to control group.Meanwhile,the levels of blood glucose,plasma lipids,and kidney function were significant enhanced.The aging model was successfully replicated according to the above results.Compared with aging model group,further experiments showed that EGCG could increase the index of spleen,thymus and brain,antioxidant capacity of liver and brain,improve learning-memory ability,and alleviate blood sugar and blood lipids,kidney function in aging mice.These suggested that EGCG could trigger certain protective effects to be against aging.(2)Effects of EGCG on gut microbiota in D-galactose-induced aging mice.The results showed that EGCG could elevated the antioxidant capacity of small intestine,the feces moisture content,the content of SCFAs in cecum,colon contents and feces,and reducd the pH value in feces when compared to aging model group.Additionally,EGCG could reduce the relative abundance of Firmicutes,and enhance the relativethe relative abundance of Ruminococcus,Coprobacillus,Prevotella,Paraprevotella and Mucispirillum in aging mice.(3)The effects of EGCG on serum and urine metabolism in aging mice using UPLC-QTOF/MS metabolomics analysis technology.The results showed that 10 serum metabolites and 27 urine metabolites had significant changes.All the differential metabolites were imported into the Metaboanalyst online database for metabolic pathway analysis,and 29 metabolic pathways were obtained.Among them,there were 7 metabolic pathways had significant changes(P<0.05).There were phenylalanine metabolism,tryptophan metabolism,pantothenate and CoA biosynthesis,aminoacyl-tRNA biosynthesis,starch and sucrose metabolism,valine,leucine and isoleucine biosynthesis,beta-Alanine metabolism.These data suggested that the anti-aging effects of EGCG were closely linked to these metabolic pathways and corresponding metabolites.(4)The effects of EGCG on intestinal and brain tissue metabolism in aging mice.The results showed that 21 intestinal tissues metabolites and 21 brain tissues metabolites had significant changes.All of these differential metabolites were imported into the Metaboanalyst online database for metabolic pathway analysis,and19 metabolic pathways were obtained.Two of them had significant changes(P<0.05)including sphingolipid metabolism and purine metabolism.These results indicated that the anti-aging mechanism of EGCG was related to sphingolipid metabolism and purine metabolism and corresponding metabolites.