title: Evaluation of antimicrobial photodynamic therapy with indocyanine green and curcumin on human gingival fibroblast cells: An in vitro photocytotoxicity investigation.
abstract: Recent investigations have suggested that antimicrobial photodynamic therapy (aPDT) can be an alternative treatment for the management of periodontal infections. However, currently there is very limited data regarding the photocytotoxicity of this method on human gingival fibroblast (HuGu) cells.
  
  
  OBJECTIVE
  The in vitro optimal concentrations of indocyanine green (ICG) and curcumin as photosensitizers (PSs) and the irradiation time of diode laser emission were evaluated by assessing the photocytotoxicity of the treatment on HuGu cells.
  
  
  METHODS
  Monolayers of HuGu cells were incubated with various final concentrations of ICG (500, 750, 1000, 1250, 1500, 1750, and 2000μg/ml) and curcumin (3, 4, 5, 10, and 20mM). Three exposure times of the diode laser (30s, 60s, and 2×30s irradiation with an interval of 1min between each) and one of exposure time of 5min for LED were tested; cell viability was determined using neutral red assay. Chlorhexidine (CHX) as a gold standard antimicrobial agent for periodontal disease was considered as a control group.
  
  
  RESULTS
  ICG and curcumin significantly reduced HuGu cell viability at concentrations below 1000μg/ml and 10mM, respectively (P<0.01). Cytotoxicity was higher when the cells were treated for 2×30s irradiation with an interval of 1min and then again exposed to the laser for 30s (2% and 0.1%). CHX demonstrated no significant reduction in HuGu cell survival.
  
  
  CONCLUSIONS
  Photocytotoxicity is influenced by PS concentration, exposure time of PS, and time of irradiation. High doses of ICG and curcumin with lowest exposure time of light source and without cytotoxic effects may be an effective strategy for aPDT as an alternative treatment for periodontal disease.
authors.affiliation: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Pourhajibagher
authors.affiliation: Laser Research Center of Dentistry, Dental Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: N
authors.initials: N
authors.lastname: Chiniforush
authors.affiliation: Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Parker
authors.affiliation: Dental biomaterials Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Shahabi
authors.affiliation: Private practice, Tehran, Iran.
authors.forename: R
authors.initials: R
authors.lastname: Ghorbanzadeh
authors.affiliation: Dental Research Center, Dental Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kharazifard
authors.affiliation: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Laser Research Center of Dentistry, Dental Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Dental Research Center, Dental Research Institute, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: abahador@tums.ac.ir.
authors.forename: A
authors.initials: A
authors.lastname: Bahador
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D003474:Curcumin / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D004359:Drug Therapy, Combination / Q000379:methods; D005347:Fibroblasts / Q000187:drug effects* / Q000382:microbiology / Q000528:radiation effects*; D005881:Gingiva / Q000187:drug effects* / Q000382:microbiology / Q000528:radiation effects*; D006801:Humans; D007208:Indocyanine Green / Q000008:administration & dosage*; D008027:Light; D010778:Photochemotherapy / Q000379:methods; D017319:Photosensitizing Agents / Q000008:administration & dosage
chemical_list: D017319:Photosensitizing Agents; D003474:Curcumin; D007208:Indocyanine Green
keywords: Cell viability; Curcumin; Cytotoxic effect; Human gingival fibroblasts; Indocyanine green; Photodynamic therapy