title: Antimicrobial activity and cytotoxicity of 3 photosensitizers activated with blue light.
abstract: BACKGROUND
  Pulp repair is less likely to occur when dentin or pulpal tissue remains infected after caries excavation. Yet there are currently few options to kill residual bacteria without damaging resident cells. The current study has evaluated the effect of 3 blue light-activated chemicals on the viability of lactobacilli, odontoblast-like cells (MDPC-23), undifferentiated pulp cells (OD21), and human embryonic stem cells (hESC H1).
  
  
  METHODS
  Bacteria were incubated for 15 minutes with curcumin, eosin Y, or rose bengal and then irradiated with blue light (240 seconds). Bacteria were labeled with LIVE/DEAD BacLight Bacterial Viability kit, and viability was assessed by fluorescence-activated cell sorting. Cytotoxicity assays were performed on MDPC-23 cells, OD21, and hESC H1 cells grown in 24-well plates and exposed to the same photosensitizer-light combination. After 24 hours, cellular response was measured by using the methyl-thiazol-diphenyl-tetrazolium assay. Results were statistically analyzed by using one-way analysis of variance and Tukey multiple comparison intervals (α = 0.05).
  
  
  RESULTS
  Bacterial viability was significantly reduced after exposure to different combinations of light and photosensitizers; mitochondrial activity of cultured cells remained unaffected when exposed to the same conditions, suggesting a good therapeutic index in vitro.
  
  
  CONCLUSIONS
  Blue light-mediated disinfection is promising for the development of new treatment strategies designed to promote pulp repair after carious exposure.
authors.affiliation: Department of Cariology and Endodontology, School of Dental Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Florence
authors.initials: F
authors.lastname: Bulit
authors.affiliation: Department of Cariology and Endodontology, School of Dental Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Grad
authors.affiliation: Department of Cariology and Endodontology, School of Dental Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Manoil
authors.affiliation: Department of Endodontics, School of Dentistry, University of Paris Diderot, Paris, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Simon
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, Washington.
authors.forename: John C
authors.initials: JC
authors.lastname: Wataha
authors.affiliation: Department of Cariology and Endodontology, School of Dental Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Anna
authors.initials: A
authors.lastname: Filieri
authors.affiliation: Department of Obstetrics and Gynaecology, Fribourg University Hospitals, Fribourg, Switzerland.
authors.forename: Anis
authors.initials: A
authors.lastname: Feki
authors.affiliation: Service of Infectious Diseases, University Hospitals of Geneva, University of Geneva, Geneva, Switzerland.
authors.forename: Jacques
authors.initials: J
authors.lastname: Schrenzel
authors.affiliation: Department of Pharmaceutics and Biopharmaceutics, School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland.
authors.forename: Norbert
authors.initials: N
authors.lastname: Lange
authors.affiliation: Department of Cariology and Endodontology, School of Dental Medicine, University of Geneva, Geneva, Switzerland. Electronic address: serge.bouillaguet@unige.ch.
authors.forename: Serge
authors.initials: S
authors.lastname: Bouillaguet
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents; D003474:Curcumin / Q000494:pharmacology / Q000633:toxicity; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects*; D053595:Embryonic Stem Cells / Q000187:drug effects*; D004801:Eosine Yellowish-(YS) / Q000494:pharmacology / Q000633:toxicity; D006801:Humans; D007778:Lactobacillus / Q000187:drug effects*; D008027:Light; D051379:Mice; D050296:Microbial Viability / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects; D009804:Odontoblasts / Q000187:drug effects*; D017319:Photosensitizing Agents / Q000494:pharmacology* / Q000633:toxicity; D012395:Rose Bengal / Q000494:pharmacology / Q000633:toxicity; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: D000890:Anti-Infective Agents; D004396:Coloring Agents; D017319:Photosensitizing Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; D012395:Rose Bengal; C022616:thiazolyl blue; D003474:Curcumin; D004801:Eosine Yellowish-(YS)
keywords: Antimicrobials; PDT; cariously exposed pulp; in vitro; pulp repair