title: Low-level laser irradiation affects the release of basic fibroblast growth factor (bFGF), insulin-like growth factor-I (IGF-I), and receptor of IGF-I (IGFBP3) from osteoblasts.
abstract: OBJECTIVE
  It was the aim of the present study to evaluate whether the laser irradiation of osteoblasts could enhance the release of growth factors including basic fibroblast growth factor (bFGF), insulin-like growth factor-I (IGF-I), and receptor of IGF-I (IGFBP3).
  
  
  BACKGROUND
  Low-level laser therapy (LLLT) has been shown to have biostimulatory effects on various cell types by enhancing production of some cytokines and growth factors.
  
  
  METHODS
  Human mesenchymal stem cells (MSCs) were seeded in osteogenic medium and differentiated into osteoblasts. Three groups were formed: in the first group (single dose group), osteoblasts were irradiated with laser (685 nm, 25 mW, 14.3 mW/cm(2), 140 sec, 2 J/cm(2)) for one time; and in the second group, energy at the same dose was applied for 2 consecutive days (double dose group). The third group was not irradiated with laser and served as the control group. Proliferation, viability, bFGF, IGF-I, and IGFBP3 levels were compared between groups.
  
  
  RESULTS
  Both of the irradiated groups revealed higher proliferation, viability, bFGF, IGF-I, and IGFBP3 expressions than did the nonirradiated control group. There was increase in bFGF and IGF-I expressions and decrease in IGFBP3 in the double dose group compared to single dose group.
  
  
  CONCLUSIONS
  The results of the present study indicate that LLLT increases the proliferation of osteoblast cells and stimulates the release of bFGF, IGF-I, and IGFBP3 from these cells. The biostimulatory effect of LLLT may be related to the enhanced production of the growth factors.
authors.affiliation: Department of Periodontology, Gülhane Military Medical Academy, Ankara, Turkey. saygunisil@hotmail.com
authors.forename: Işıl
authors.initials: I
authors.lastname: Saygun
authors.forename: Nejat
authors.initials: N
authors.lastname: Nizam
authors.forename: Ali Uğur
authors.initials: AU
authors.lastname: Ural
authors.forename: Muhittin Abdülkadir
authors.initials: MA
authors.lastname: Serdar
authors.forename: Ferit
authors.initials: F
authors.lastname: Avcu
authors.forename: Tolga Fikret
authors.initials: TF
authors.lastname: Tözüm
mesh_terms: D049109:Cell Proliferation / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004797:Enzyme-Linked Immunosorbent Assay; D016222:Fibroblast Growth Factor 2 / Q000096:biosynthesis / Q000528:radiation effects*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000096:biosynthesis / Q000528:radiation effects*; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis / Q000528:radiation effects*; D028022:Low-Level Light Therapy / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000502:physiology / Q000528:radiation effects; D010006:Osteoblasts / Q000502:physiology / Q000528:radiation effects*; D011829:Radiation Dosage; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
chemical_list: C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D016222:Fibroblast Growth Factor 2; D007334:Insulin-Like Growth Factor I