The Exosomal MiR-205-5p Derived From Periodontal Ligament Stem Cells Regulates The Th17/Treg Balance In Periodontitis By Targeting XBP1

Objective:Chronic periodontitis is a common and complex inflammatory disease caused by a variety of periodontal pathogens such as porphyromonas gingivails.Chronic periodontitis occurs on specific teeth,usually at the leaf end of the tooth,and adjacent teeth are not affected.The onset of periodontitis is very regular,the initial stage is extremely serious,there is a long-term stable period,during which there will be many times of relatively mild recurrence.From 1990 to 2020,the incidence of periodentitis increased by 57.3%,and is still rising year by year.Periodentitis clinical manifestations of loose teeth,gingival swelling or bleeding,alveolar bone absorption,become the main cause of modern dentition defects.At present,complete elimination of infection and inflammation in periodontitis is the ultimate treatment goal,but more effective treatment is needed to achieve this goal.Therefore,it is very important to study the pathogenesis of periodontitis and optimize the treatment plan.This is also the focus of current stomatologists.Exosomes have been identified as small secretory organelles rich in avatiety of organics(miRNAs and proteins)that are released from cells into the extracellular environment.Multiple exosome mirnas have unique characteristics or functions in periodontitis.miR-1246 in exosomes secreted by dental pulp stem cells promotes the transition of periodontal tissues from pro-inflammatory to anti-inflammatory phenotypes.During orthodontic tooth movement,the expression of miRNA-29 in human gingival crevicular fluid is increase,and miRNA-29 can be used as a biomarker of periodontal remodeling.Mechanical stress-induced exosome miR-181b-5p promotes the proliferation of periodontal membrane stem cells(PDLSC).The increase of exosome miR-200c also inhibited the proinflammatory cell therapy of lipopolysaccharide(LPS)-induced periodontitis mice.In addition,exosome miR-205 is closely associated with many diseases.Exosome miR-205-5p is a biomarker for the diagnosis of non-small cell carcinoma and clear cell renal carcinoma.Exosome miR-205 derived from ovarian cancer cells promotes metastasis.However,the regulatory mechanism of exosome miR-205 on LPS-inducd periodontitis remain unclear.In this study,the pathological model of periodontitis was analyzed by animal experiment and cell experiment,using ELISA,Flowcytometry,QPCR,Western blot and other immunoassay techniques were used to analyze and explain the effect of exosome miR-205-5P derived from periodontal membrance stem cells on periodontitis and the effect and mechanism of exosome miR-205-5p regulating Th17/Tregs of periodontitis host by targeting XBP1,so as to provide reference for subsequent studies.Methods:this study consists of the following1.Exploration of the change of exosome miR-205-5p and Th17/Treg ratio in the progression of chronic periodontitis.We first established an animal model of periodontitis.The lymphocytes and periodontal membrance stem cells were extracted from gingival and peripheral blood of model animals and healthy animals,and the change trend and characteristics of CD4~+T cells in different tissues under different conditions were analyzed.Flow cytometry,ELISA and q PCR were used to evaluate the content of inflammatory factors in CD4~+T cells at gene and protein levels.This part intends to reveal the changes of CD4~+T cells(Th17/Treg)in the host of periodontitis and analyze the inflammatory response of exosome miR-205-5p to chronic periodontitis.2.Analysis of biological relationship between exosome miR-205-5p and XBP1 in the progression of chronic periodontitis.The internal relationship between miR-205-5p and X-box binding protein(XBP1)was determined by double luciferase reporting method RIP method and RNA down method in the previous experiment,so as to clarify the passage of exosome miR-205-5p from periodontal membrance stem cells through XBP1 is the regulatory effect of vector on local host immunity during the development of periodontitis.3.The mechanism by which exosome miR-205-5p regulates Th17/Treg balance by targeting XBP1 in the progression of chronic periodontitis.CD4~+T cells from healthy animals and periodontitis animals were isolated and co-cultured under normal condition,LPS condition and LPS+Exo condition respectively.ELISA method was used to analyze the concentration of IL-10,RORvt and IL-17A in each culture medium,and q PCR method was used to detect IL-10,Foxp3,IL-17A in cells m RNA and RORvt expression level.Western blot was used to identify periodontal membrace cells and exosomes and their relationship with the above indexes.This part of the study intends to explain the mechanism of targeting XBP1 to regulate Th17/Treg balance by exosome miR-205-5P transduction.Results:1.The expression of miR-205-5p was reduced in LPS-induced PDLSC-derived exosomes.2.Exo-miR-205-5p improves inflammatory response and regulates Th17/Treg cell balance in rats with periodontitis.3.XBP1 is the target gene of miR-205-5p and is down-regulation by miR-205-5p.4.Exosome miR-205-5p regulates LPS-induced inflammation and Treg/Th17imbalance by targeting XBP1.Conclusions:Exosome miR-205-5p derived from periodontal stem cells can reduce periodontal inflammation and regulate.Th17/Treg balance in chronic periodontitis by targeting XBP1.This study provides a new therapeutic target for the treatment of chronic periodontitis.