Oligonucleotides On The Expression Of Inflammatory Mediators In RAW264.7 Cells Stimulated By Pg Lipopolysaccharide

Periodontitis is a chronic inflammatory disease caused by periodontal pathogen infection.People from different countries,regions,ethnic groups and people of different ages can suffer from this kind of disease.The prevalence of periodontal disease in China is as high as 80%to 90%,which is the main reason for adults to lose their teeth[1].As a main pathogen causing periodontitis,Porphyromonas gingivalis can produce a variety of virulence factors,and at the same time cause inflammation and destruction of soft and hard tissues around the tooth.As an important component of innate immunity,macrophages are effector cells that perform innate immunity and are widely distributed in tissues.Recent studies have suggested that periodontitis is an infectious disease,and the periodontal immune response stimulated by periodontal pathogens can cause inflammation and destruction of periodontal soft and hard tissues.Oligodeoxynucleotide(ODN)is a polynucleotide chain containing tens of nucleotide monomers that can be taken up by cells in a receptor-mediated manner.By artificially designing and modifying the ODN,it is chemically stable,which can quickly enter immune cells,activate the immune system in the body,and induce a rapid anti-infective immune response.By modifying the phosphorylation of ODN,it can resist the digestion of nuclease,have stability in vivo,and also increase the uptake rate of cells.ODN has become a research focus in basic medical fields such as immunology in recent years due to its low biotoxicity,ease of artificial synthesis,and chemically stable properties.Therefore,this study simulates inflammatory microenvironmental conditions in vitro by detecting the expression levels of inflammatory mediators associated with RAW264.7 cells in mouse macrophages stimulated by P.gingivalis lipopolysaccharide(Pg-LPS)under different ODN treatments.Changes are made to investigate the effect of specific sequence ODN on the expression of inflammatory mediators in RAW264.7 cells stimulated by Pg-LPS.Methods:The mouse mononuclear macrophage cell line RAW264.7 was selected,resuscitated,cultured,passaged and used in HG-DMEM medium.RAW264.7 cells in logarithmic growth phase were inoculated into the cell plate,stimulated with Pg-LPS at a concentration of 10 ?g/ml,and at the same time added different sequence ODN(working concentration 1?g/ml)named MTO1,MS19,YW001,FC004,YW002 and 2006 respec-tively.Equal volume of PBS was blank control groups and RAW264.7 cells stimulated with Pg-LPS without ODN were positive control groups.All groups were cultured to 4 period of time in order to detect(12h,24h,48h and 72h).CCK8 method was used for detection of cell viability of Pg-LPS-stimulated RAW264.7 macrophages after added ODN.ELISA assayed the effect of ODN on specific inflammatory factors TNF-a and IL-6 expression of Pg-LPS-stimulated RAW264.7 macroph-ages.And the effect of ODN on the expression of NO of RAW264.7 cells stimulated by Pg-LPS was detected by microplate method.Results:Compared with the Pg-LPS group,MTO1 and MS 19 inhibited the expression of TNF-a and IL-6 at 12h and 24;MTO1,MS 19,YW001,FC004,YW002,2006 inhibited the expression of NOat 48h and 72h.Conclusion:(1)MT01 and MS 19 down-regulated the expression of TNF-a and IL-6 in RAW264.7 cells at the early stage of inflammation,and down-regulated the synthesis of NO in RAW264.7 cells at the late stage of inflammation.(2)YW001,FC004,YW002,2006 down-regulated the synthesis of NO in RAW264.7 cells at the late stage of inflammation.