title: Cell attachment modulation by radiation from a pulsed light diode (lambda = 820 nm) and various chemicals.
abstract: OBJECTIVE
  Adhesive interactions between cells and extracellular matrices play a regulative role in wound repair processes. The objective of this investigation is to study the mechanisms of light action on cellular adhesion in vitro. The adhesion of HeLa cells to a glass matrix is evaluated after irradiation with a pulsed near-infrared (IR) diode and treatment with various chemicals.
  
  
  METHODS
  A semiconductor diode (820 +/- 10 nm, 10Hz, 16--120 J/m(2)) is used for irradiation of the cell suspension. In parallel experiments, various chemicals (mannitol, melatonin, ethanol, ascorbic acid, superoxide dismutase, catalase, rotenone, azide, dinitrophenol (DNP), methylene blue, and hydrogen peroxide) are added to the cell suspension before or after the irradiation procedure. The cell-glass adhesion is studied by using the adhesion assay technique (Lasers Surg. Med. 1996;18:171).
  
  
  RESULTS
  It has been found that cell-glass adhesion increases in a dose-dependent manner after irradiation. The treatment of the cells with antioxidants (free radical scavengers), e.g., mannitol, melatonin, ethanol, and ascorbic acid, as well as with the ionophore DNP, eliminated the light effect. The respiratory chain inhibitors rotenone and azide strongly modified the light effect, depending on the dose. The oxidative agents hydrogen peroxide (in a low concentration) and methylene blue increased the cell adhesion. Superoxide dismutase did not modify the light effect. The effect of the catalase (stimulative or suppressive) was dependent on its concentration and treatment sequence. Preirradiation was found to decrease (or normalize to the control level) the suppressive effects of some chemicals.
  
  
  CONCLUSIONS
  The results obtained are evidence that first, pulsed IR radiation with certain parameters modulates the cell-matrix attachment. second, free radical and redox processes are involved in the cell-matrix interaction, probably at some stage(s) of the photosignal transduction. Third, both types of the primary reactions in the respiratory chain, namely, the increase of the electron flow and production of the reactive oxygen species, cause a transient oxidative stress in the cytoplasm.
authors: Institute of Laser and Informatic Technologies, Russian Academy of Sciences, 142190 Troitsk, Moscow Region, Russian Federation. karu@isan.troisk.ru
authors: T I
authors: TI
authors: Karu
authors: L V
authors: LV
authors: Pyatibrat
authors: G S
authors: GS
authors: Kalendo
mesh_terms: D001205:Ascorbic Acid / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects* / Q000528:radiation effects*; D002478:Cells, Cultured; D004140:Dinitrophenols / Q000494:pharmacology; D004307:Dose-Response Relationship, Radiation; D000431:Ethanol / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007287:Inorganic Chemicals / Q000494:pharmacology*; D053685:Laser Therapy; D008353:Mannitol / Q000494:pharmacology; D008550:Melatonin / Q000494:pharmacology; D008751:Methylene Blue / Q000494:pharmacology; D009930:Organic Chemicals / Q000494:pharmacology*; D011336:Probability; D012016:Reference Values; D012402:Rotenone / Q000494:pharmacology; D012680:Sensitivity and Specificity; D013482:Superoxide Dismutase / Q000494:pharmacology
chemical_list: D004140:Dinitrophenols; D007287:Inorganic Chemicals; D009930:Organic Chemicals; D012402:Rotenone; D000431:Ethanol; D008353:Mannitol; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase; D008550:Melatonin; D001205:Ascorbic Acid; D008751:Methylene Blue