title: Docosahexaenoic acid attenuates oxidative stress and protects human gingival fibroblasts against cytotoxicity induced by hydrogen peroxide and butyric acid.
abstract: OBJECTIVE
  The oxidative burst of the host cells associated with bacterial pathogen infection contributes to the destruction of periodontal tissue. The present study investigates the effect of docosahexaenoic acid (DHA) on human gingival fibroblast (HGF) viability and ROS generation.
  
  
  METHODS
  The cell viability by MTT assay, ROS level using H2DCF-DA probe, and protein thiol content were measured in HGFs after 24h preincubation with different concentrations of DHA followed by treatment with H2O2. The cell death rate was determined by Annexin V/propidium iodide staining, and mitochondrial membrane potential (ΔΨm) was examined by MitoTracker Red probe in H2O2- and butyric acid-treated HGFs. The fatty acid composition of plasma membranes after incubation with DHA was determined by gas chromatography mass spectrometry.
  
  
  RESULTS
  DHA preincubation in a dose-dependent manner increased the viability of HGFs exposed to H2O2 and decreased ROS generation compared to the control cells. In HGFs preincubated with 30μM DHA, the ΔΨm significantly increased in both H2O2- and butyric acid-treated cells. Moreover, incubation with DHA preserved the protein thiol level as effectively as N-acetylcysteine. Application of 50μM DHA increased the quantity of viable cells, decreased the number of necrotic cells after H2O2 treatment, and protected HGFs from apoptosis induced by butyric acid. DHA in the plasma membranes of these HGFs represented about 6% of the total amount of fatty acids.
  
  
  CONCLUSIONS
  These results demonstrate that enrichment of HGFs with DHA reduces ROS generation and enhances the mitochondrial membrane potential protecting the fibroblasts against cytotoxic factors.
authors.affiliation: Department of Cell-to-Cell Communication, Medical University of Lodz, Lodz, Poland. Electronic address: emilia.zgorzynska@e.umed.lodz.pl.
authors.forename: Emilia
authors.initials: E
authors.lastname: Zgorzynska
authors.affiliation: Department of General Dentistry, Medical University of Lodz, Lodz, Poland.
authors.forename: Anita
authors.initials: A
authors.lastname: Wierzbicka-Ferszt
authors.affiliation: Department of Cell-to-Cell Communication, Medical University of Lodz, Lodz, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Dziedzic
authors.affiliation: Department of Molecular Pathology and Neuropathology, Medical University of Lodz, Lodz, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Witusik-Perkowska
authors.affiliation: Department of Cell-to-Cell Communication, Medical University of Lodz, Lodz, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Zwolinska
authors.affiliation: Department of General Dentistry, Medical University of Lodz, Lodz, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Janas
authors.affiliation: Department of Cell-to-Cell Communication, Medical University of Lodz, Lodz, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Walczewska
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D020148:Butyric Acid / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D005227:Fatty Acids / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D009336:Necrosis; D018384:Oxidative Stress / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D017382:Reactive Oxygen Species; D020148:Butyric Acid; D004281:Docosahexaenoic Acids; D006861:Hydrogen Peroxide
keywords: Docosahexaenoic acid; Gingival fibroblasts; Mitochondrial membrane potential; ROS