title: Effect of photobiomodulation on vinblastine-poisoned murine HERS cells.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of near-infrared (NIR) photobiomodulation on the proliferation and glutathione levels in murine Hertwig's epithelial root sheath (HERS) cells after poisoning with vinblastine.
  
  
  BACKGROUND
  Photobiomodulation has been shown to improve wound healing in a number of animal models. There have been no studies on the effect of photobiomodulation on cancer-related chemotherapy injury to the cells that initiate tooth root growth.
  
  
  METHODS
  Control groups consisted of murine HERS cells without vinblastine (VB-) and cells with vinblastine at 10, 20, and 30 ng/mL (VB10, VB20, and VB30). Experimental groups consisted of these same groups with light therapy (VB-L, VB10L, VB20L, and VB30L). The cells were exposed to vinblastine for 1 h. Photobiomodulation consisted of a 75-cm(2) gallium-aluminum-arsenide light-emitting diode (LED) array at an energy density of 12.8 J/cm(2), delivered with 50 mW/cm(2) power over 256 s.
  
  
  RESULTS
  Vinblastine alone significantly decreased HERS cell proliferation and glutathione levels at all concentrations (VB10 [-55%, p < 1.0 × 10(-8)]; VB20 [-72%, p < 1.0 × 10(-9)]; VB30 [-80%, p < 1.0 × 10(-10)]; and VB10 [-36%, p < 0.0001]; VB20 [-49%, p < 1.0 × 10(-6)]; VB30 [-53%, p < 1.0 × 10(-7)] respectively). Photobiomodulation significantly increased cell proliferation at all levels of vinblastine exposure (VB10L [+50%, p < 0.0001]; VB20L [+45%, p < 0.05]; VB30 [+39%, p < 0.05]) but not of the control (+22%, p = 0.063). The photobiomodulation significantly increased glutathione production in all concentrations of vinblastine except 20 ng/mL (VB10L [+39%, p = 0.007]; VB20L [+19%, p = 0.087]; VB30 [+14%, p = 0.025]) and the control (+12%, p = 0.13).
  
  
  CONCLUSIONS
  Photobiomodulation demonstrated an improvement in proliferation and glutathione levels in vinblastine-poisoned murine HERS cells.
authors.affiliation: Marquette University, Milwaukee, Wisconsin, USA. brian.hodgson@marquette.edu
authors.forename: B D
authors.initials: BD
authors.lastname: Hodgson
authors.forename: B
authors.initials: B
authors.lastname: Pyszka
authors.forename: M M
authors.initials: MM
authors.lastname: Henry
authors.forename: E
authors.initials: E
authors.lastname: Buchmann
authors.forename: H T
authors.initials: HT
authors.lastname: Whelan
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects* / Q000528:radiation effects*; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D051379:Mice; D010789:Phototherapy / Q000295:instrumentation*; D014092:Tooth Root / Q000166:cytology* / Q000378:metabolism; D014747:Vinblastine / Q000506:poisoning*; D014945:Wound Healing / Q000502:physiology
chemical_list: D014747:Vinblastine; D005978:Glutathione