title: Photodynamic effects on human periodontal-related cells in vitro.
abstract: BACKGROUND
  Photodynamic therapy (PDT) may be especially effective in combination with conventional periodontal therapy by its antimicrobial activities, but PDT may also exhibit other mechanisms that promote the healing of periodontal tissue. Therefore, the purpose of the present study was to evaluate the photodynamic effect of PDT on human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (hFBs) in vitro and other possible mechanisms to promote periodontal healing.
  
  
  METHODS
  The proliferation of hPDLCs and hFBs was assessed by MTT assay. Cell attachment on cementum slices of hPDLCs and hFBs was evaluated by MTT assay. Type I collagen synthesis of hPDLCs and hFBs was analyzed using enzyme linked immunosorbent assay. The alkaline phosphatase (ALP) activity in hPDLCs was measured by p-nitrophenyl phosphate substrate reactions.
  
  
  RESULTS
  PDT treatment induced constant time-dependent growth of hPDLCs and hFBs at 24h, 72h and 6 days (P<0.05). PDT treatment also promoted time-dependent hPDLCs and hFBs attachment on the cementum slices at 24h, 72h and 6 days compared to the controlled cells (P<0.05). Type I collagen synthesis of hPDLCs and hFBs was markedly stimulated by PDT in a time-dependent manner (P<0.05). Likewise, a significant increase in the specific ALP activity in hPDLCs was observed (P<0.05).
  
  
  CONCLUSIONS
  The findings of this study indicate that PDT exhibited no cytotoxicity to hPDLCs or hFBs. Instead, it stimulated proliferation, attachment and collagen synthesis of hPDLCs and hFBs and ALP activity of hPDLCs. These effects might signal similar PDT activity on periodontal-related cells, and expanding the scope of its potential therapeutic utilization is very appealing.
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, The First Outpatient Center, Xishenku Avenue 37, Xicheng District, Beijing 100034, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Qiao
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, The First Outpatient Center, Xishenku Avenue 37, Xicheng District, Beijing 100034, China.
authors.forename: Shiying
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, The First Outpatient Center, Xishenku Avenue 37, Xicheng District, Beijing 100034, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wen
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, The First Outpatient Center, Xishenku Avenue 37, Xicheng District, Beijing 100034, China. Electronic address: jhuimei2013@aliyun.com.
authors.forename: Huimei
authors.initials: H
authors.lastname: Jia
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects / Q000502:physiology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005881:Gingiva / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008751:Methylene Blue / Q000494:pharmacology*; D010513:Periodontal Ligament / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000494:pharmacology
chemical_list: D017319:Photosensitizing Agents; D008751:Methylene Blue
keywords: Human gingival fibroblasts; Human periodontal ligament cells; Periodontal therapy; Photodynamic therapy