title: The Triple Functions of D2 Silencing in Treatment of Periapical Disease.
abstract: BACKGROUND
  Dental caries is the most widespread chronic infectious disease. Inflammation in pulp tissues caused by dental caries will lead to periapical granulomas, bone erosion, loss of the tooth, and severe pain. Despite numerous efforts in recent studies to develop effective treatments for dental caries, the need for a potent therapy is still urgent.
  
  
  METHODS
  In this study, we applied a gene-based therapy approach by administering recombinant adeno-associated virus (AAV)-mediated Atp6v0d2 (d2) RNA interference knockdown of d2 gene expression to prevent periapical bone loss and suppress periapical inflammation simultaneously.
  
  
  RESULTS
  The results showed that d2 depletion is simultaneously capable of reducing bone resorption with 75% protection through reducing osteoclasts, enhancing bone formation by increasing osterix expression, and inhibiting inflammation by decreasing T-cell infiltration. Notably, AAV-mediated gene therapy of d2 knockdown significantly reduced proinflammatory cytokine expression, including tumor necrosis factor α, interferon-γ, interleukin-1α, and interleukin 6 levels in periapical diseases caused by bacterial infection. Quantitative real-time polymerase chain reaction revealed that d2 knockdown reduced osteoclast-specific functional genes (ie, Acp5 and Ctsk) and increased osteoblast marker genes (ie, Osx and Opg) in periapical tissues.
  
  
  CONCLUSIONS
  Collectively, our results showed that AAV-mediated d2 depletion in the periapical lesion area can prevent the progression of endodontic disease and bone erosion while significantly reducing the inflammatory over-response. These findings show that the depletion of d2 simultaneously reduces bone resorption, enhances bone formation, and inhibits inflammation caused by periapical diseases and provide significant insights into the potential effectiveness of AAV-sh-d2-mediated d2 silencing gene therapy as a major endodontic treatment.
authors.affiliation: Department of Orthodontics, Shanghai Stomatological Disease Centre, Shanghai, People's Republic of China; Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Jie
authors.initials: J
authors.lastname: Pan
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Jue
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Liang
authors.initials: L
authors.lastname: Hao
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Guochun
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Diep N
authors.initials: DN
authors.lastname: Nguyen
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Life Science College, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Orthodontics, Shanghai Stomatological Disease Centre, Shanghai, People's Republic of China.
authors.forename: Yuehua
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, People's Republic of China.
authors.forename: Zhihe
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama. Electronic address: yipingli@uabmc.edu.
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Li
authors.affiliation: Department of Pathology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama. Electronic address: weichen@uabmc.edu.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000235:genetics / Q000503:physiopathology; D016207:Cytokines / Q000378:metabolism / Q000502:physiology; D000229:Dependovirus / Q000235:genetics; D055786:Gene Knockout Techniques; D015316:Genetic Therapy / Q000379:methods*; D051379:Mice; D008807:Mice, Inbred BALB C; D010010:Osteoclasts / Q000378:metabolism / Q000502:physiology; D010012:Osteogenesis / Q000235:genetics / Q000502:physiology; D010483:Periapical Diseases; D013601:T-Lymphocytes / Q000502:physiology; D025262:Vacuolar Proton-Translocating ATPases / Q000378:metabolism / Q000502:physiology*
chemical_list: D016207:Cytokines; C542312:Atp6v0d2 protein, mouse; D025262:Vacuolar Proton-Translocating ATPases
keywords: Bacteria; bone loss; caries treatment; endodontics; gene therapy; inflammation