Effect And Mechanism Of Tilapia Head Glycolipid On DSS-induced Colitis In Mice

In recent years,the incidence of inflammatory bowel disease(IBD)has been gradually increasing due to multiple factors.As long-term drug treatment can cause different degrees of physical side effects,nutritional diet intervention has become a new direction and trend to prevent and alleviate IBD.Recently,there have been extensive reports on the prevention of inflammatory bowel disease effects of polyphenols,polysaccharides and lipids.In particular,the research results on the occurrence,development and regulation of functional lipids in inflammatory bowel disease have increased significantly.In order to explore the anti-inflammatory effect and mechanism of glycolipids in fish heads,the fish heads were isolated from the fish heads produced during the processing of tilapia,which is abundant in Hainan.Tilapia head glycolipid(TH-GL)was extracted,and TH-GL was used as a reseach object to explore its effect on the inflammatory effect of Dextran Sulfate Sodium Salt(DSS)in C57BL/6 mice.The protective effect and mechanism of the enteropathy model,the specific research content is as follows:1.The regulatory effect of th-GL on inflammatory injury in mice with colitisTo explore the TH-GL anti-inflammatory modulating activity in mice.TH-GL was obtained by extracting total lipid from tilapia fish head and performing silica gel column chromatography,and then establised DSS-induced C57 BL / 6 mice inflammatory bowel disease model,conduct TH-GL therapeutic intervention experiment.The results showed that TH-GL had no adverse effects on normal mice.Compared with the control group,the weight and Disease activity index,DAI)in DSS group decreased significantly,and the colon shortened,flagging,the number of loose stools increased and bloody stools appeared.After different doses of TH-GL were given,the weight of mice increased reversely,DAI score increased,stool formed,intestinal injury and colon shortening were inhibited.Histopathological staining showed that the destruction of crypt in colon tissue decreased,glands arranged orderly,and infiltration degree of inflammatory cells such as neutrophils decreased after TH-GL feeding.Determination of tumor necrosis factor-α(Tumor necrosis factor-α,TNF-α),interleukin-6(IL-6)and interference in mouse colon tissue and serum by q RT-PCR and ELISA methods,respectively Interferon-γ(Interferon-γ,IFN-γ)and other pro-inflammatory cytokines and interleukin-10(Interleukin-10,IL-10)secretion and gene expression,TH-GL intervention can reduce inflammation in mice with enteritis The expression of sex cytokines and their m RNA,and increase the concentration of IL-10 in the serum,maintain the balance of pro-inflammatory and anti-inflammatory cytokines in the serum.Western Blot(WB)showed that TH-GL can regulate the occurrence and development of inflammation by down-regulating the expression of key proteins in NF-κB signal pathway mediated by TNF-α in colon tissue of enteritis mice.2.The repairing effect of TH-GL on intestinal barrier in mice with colitisWith DSS-induced inflammatory bowel disease in mice as the model,TH-GL treatment intervention experiment was conducted to explore the protective effect of TH-GL on intestinal epithelial barrier in colitis mice.The results showed that TH-GL could restore colon integrity and inhibit ulcer erosion.AB-PAS staining showed that mucus secretion from colon epithelium decreased in model group,while TH-GL significantly increased mucus secretion,suggesting that TH-GL can protect mucus-secreting cells.Meanwhile,IHC,WB,q RT-PCR analysis showed that TH-GL significantly increased MUC2 protein expression and decreased colon injury.DSS can destroy the tight junction of mouse intestinal epithelial cells,and TH-GL can protect the tight junction of intestinal epithelial cells,and significantly increase the expression of ZO-1 and Occludin protein.TH-GL can reduce the membrane permeability and repair the intestinal barrier injury in colitis mice by reducing the displacement of tight junction structure.3.The improvement of th-GL on gut microbiota in mice with colitisIn order to explore the effect of TH-GL on the abundance and diversity of gut microbiota in mice with colitis,16 s r RNA sequencing technology was used to detect the changes of bacterial content in feces of mice.The results showed that TH-GL could significantly improve α diversity and β diversity of gut microbiota in mice with colitis induced by modeling,such as Simpson index,Shannon index,Chao1 index and PCOA,etc.The composition and structure of gut microbiota of mice treatment with TH-GL were closer to the control group and deviated from the model group.Enterobacteriaceae and Gammaproteobacteria are the main bacteria causing colon inflammation.TH-GL significantly reduced the colonization of Gammaproteobacteria and Enterobacteriaceae in the intestinal tract of colitis mice,and promoted the enrichment of Akkermansia,Prevotellaceae,Oscillospira,Allobaculum,Bifidobacterium and Coprococcus.TH-GL can further regulate colitis in mice by improving gut microbiota,reducing harmful bacteria and increasing the abundance of beneficial bacteria.4.The effect of th-GL on intestinal metabolites in mice with colitisIn this study,in order to explore the effect of TH-GL on intestinal metabolites in mice with colitis,a mouse model of ulcerative colitis was established.UHPLC-Q-TOF-MS technology was used to detect the changes of gut metabolites in mice with ulcerative colitis and mice treated with TH-GL.and the differential metabolites were targeted,and metabolic pathways and marker enrichment analysis were performed in the KEGG database.According to the analysis,there are 40 kinds of different metabolites,including 2-oxodaipate,Histamine,L-Glutamate and Taurocholate,which mainly involve histidine metabolism,d-glutamine and D-glutamic acid metabolism,arginine biosynthesis,primary bile acid synthesis,tryptophan metabolism and alanine,aspartate and glutamic acid metabolism.The results showed that TH-GL could improve colon inflammation by regulating the balance of multiple metabolic pathways.